feat(ops): pipeline-health dashboard

- Add a /health ops page: snapshot freshness (last-capture-at, colour-coded), 24h vs
  total snapshots + anomalies, events tracked, sports covered, and the four worker
  on/off states. Nav entry under System; localized en+ru.
- New IPipelineHealthService + ISnapshotRepository.GetLatestCapturedAtAsync (max
  CapturedAt via indexed ORDER BY/LIMIT 1), with a real-SQLite round-trip test.

src/Marathon.Application/Abstractions/ISnapshotRepository.cs

@@ -22,6 +22,12 @@ public interface ISnapshotRepository
     /// </summary>
     Task<int> CountSinceAsync(DateTimeOffset since, CancellationToken ct = default);
 
+    /// <summary>
+    /// The most recent snapshot capture time across all events, or <c>null</c> when the
+    /// store is empty. Backs the pipeline-health freshness indicator.
+    /// </summary>
+    Task<DateTimeOffset?> GetLatestCapturedAtAsync(CancellationToken ct = default);
+
     Task<IReadOnlyList<OddsSnapshot>> ListByEventAsync(
         EventId eventId,
         DateTimeOffset from,

src/Marathon.Infrastructure/Persistence/Repositories/SnapshotRepository.cs

@@ -27,6 +27,18 @@ internal sealed class SnapshotRepository : ISnapshotRepository
             .CountAsync(ct);
     }
 
+    public async Task<DateTimeOffset?> GetLatestCapturedAtAsync(CancellationToken ct = default)
+    {
+        // O-format TEXT sorts lexically == chronologically (see SqliteDateText), so the
+        // max CapturedAt is the most recent capture. ORDER BY + LIMIT 1 pushed to SQLite.
+        var latest = await _db.Snapshots.AsNoTracking()
+            .OrderByDescending(s => s.CapturedAt)
+            .Select(s => s.CapturedAt)
+            .FirstOrDefaultAsync(ct);
+
+        return latest is null ? null : SqliteDateText.Parse(latest);
+    }
+
     public async Task<IReadOnlyList<OddsSnapshot>> ListByEventAsync(
         EventId eventId,
         DateTimeOffset from,

src/Marathon.UI/Components/NavBody.razor

@@ -57,6 +57,10 @@
         <MudIcon Icon="@Icons.Material.Outlined.FileDownload" Size="Size.Small" />
         <span>@L["Nav.Export"]</span>
     </NavLink>
+    <NavLink class="m-nav__link" href="health">
+        <MudIcon Icon="@Icons.Material.Outlined.MonitorHeart" Size="Size.Small" />
+        <span>@L["Nav.Health"]</span>
+    </NavLink>
     <NavLink class="m-nav__link" href="settings">
         <MudIcon Icon="@Icons.Material.Outlined.Tune" Size="Size.Small" />
         <span>@L["Nav.Settings"]</span>

src/Marathon.UI/Pages/Health.razor

@@ -0,0 +1,93 @@
+@page "/health"
+@inject IStringLocalizer<SharedResource> L
+@inject IPipelineHealthService HealthService
+@inject ILogger<Health> Logger
+
+<PageTitle>@L["App.Title"] · @L["Nav.Health"]</PageTitle>
+
+<section class="m-shell">
+    <header class="m-rise m-rise-1" style="display: grid; gap: var(--m-space-3); max-width: 880px;">
+        <span class="m-kicker">@L["Health.Kicker"]</span>
+        <h1 class="m-display" style="font-size: clamp(2rem, 4vw, 3rem);">@L["Health.Title"]</h1>
+        <p style="color: var(--m-c-ink-soft); max-width: 60ch;">@L["Health.Lede"]</p>
+    </header>
+
+    <hr class="m-rule--double" />
+
+    <div class="m-rise m-rise-2" data-test="health-freshness"
+         style="display: inline-flex; align-items: center; gap: 10px; font-family: var(--m-font-mono); font-size: 0.8125rem; text-transform: uppercase; letter-spacing: 0.12em;">
+        <span style="width: 10px; height: 10px; border-radius: 50%; background: @FreshnessColor;"></span>
+        <span style="color: var(--m-c-ink-soft);">@L["Health.LastCapture"]:</span>
+        <span style="color: @FreshnessColor;">@FreshnessText</span>
+    </div>
+
+    <div class="m-grid--three m-rise m-rise-2" style="margin-top: var(--m-space-5);">
+        <StatCard Label="@L["Health.Stat.Snapshots"]"
+                  Value="@_health.SnapshotsLast24h.ToString("N0")"
+                  Delta="@string.Format(CultureInfo.CurrentCulture, L["Health.Total"].Value, _health.SnapshotsTotal)" />
+        <StatCard Label="@L["Health.Stat.Anomalies"]"
+                  Value="@_health.AnomaliesLast24h.ToString("N0")"
+                  Delta="@string.Format(CultureInfo.CurrentCulture, L["Health.Total"].Value, _health.AnomaliesTotal)"
+                  Anomaly="true" />
+        <StatCard Label="@L["Health.Stat.Events"]" Value="@_health.EventsTracked.ToString("N0")" />
+        <StatCard Label="@L["Health.Stat.Sports"]" Value="@_health.SportsCovered.ToString()" />
+    </div>
+
+    <aside class="m-card m-card--accented m-rise m-rise-3" style="margin-top: var(--m-space-6);">
+        <span class="m-kicker">@L["Health.Workers"]</span>
+        <ol style="list-style: none; padding: 0; margin: var(--m-space-4) 0 0; display: grid; gap: var(--m-space-3);">
+            <PipelineStep Index="01" Label="@L["Health.Worker.Schedule"]" Status="@WorkerStatus(_health.UpcomingPollerEnabled)" />
+            <PipelineStep Index="02" Label="@L["Health.Worker.Live"]" Status="@WorkerStatus(_health.LivePollerEnabled)" />
+            <PipelineStep Index="03" Label="@L["Health.Worker.Detection"]" Status="@WorkerStatus(_health.AnomalyDetectionEnabled)" />
+            <PipelineStep Index="04" Label="@L["Health.Worker.Results"]" Status="@WorkerStatus(_health.ResultsPollerEnabled)" />
+        </ol>
+    </aside>
+
+    @if (!_health.HasData)
+    {
+        <p class="m-rise m-rise-3" data-test="health-empty"
+           style="margin-top: var(--m-space-5); color: var(--m-c-ink-soft);">
+            @L["Health.Empty"]
+        </p>
+    }
+</section>
+
+@code {
+    private PipelineHealth _health = PipelineHealth.Empty;
+
+    protected override async Task OnInitializedAsync()
+    {
+        try
+        {
+            _health = await HealthService.GetAsync(CancellationToken.None);
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError(ex, "Health: failed to load pipeline health.");
+        }
+    }
+
+    private static string WorkerStatus(bool enabled) => enabled ? "ok" : "idle";
+
+    private double? MinutesSinceLastCapture =>
+        _health.LastSnapshotAt is { } at ? (MoscowTime.Now - at).TotalMinutes : null;
+
+    private string FreshnessText
+    {
+        get
+        {
+            if (MinutesSinceLastCapture is not { } mins)
+                return L["Health.LastCapture.Never"];
+            return string.Format(CultureInfo.CurrentCulture, L["Health.MinutesAgo"].Value, (int)Math.Max(0, mins));
+        }
+    }
+
+    // Green when fresh (<15 min), amber when slowing (<60 min), signal-red when stale.
+    private string FreshnessColor => MinutesSinceLastCapture switch
+    {
+        null => "var(--m-c-ink-soft)",
+        < 15 => "var(--m-c-positive)",
+        < 60 => "var(--m-c-accent)",
+        _ => "var(--m-c-anomaly)",
+    };
+}

src/Marathon.UI/Resources/SharedResource.en.resx

@@ -65,6 +65,7 @@
   <data name="Nav.Results"><value>Results</value></data>
   <data name="Nav.Settings"><value>Settings</value></data>
   <data name="Nav.Export"><value>Export</value></data>
+  <data name="Nav.Health"><value>Health</value></data>
 
   <data name="Home.Kicker"><value>Briefing</value></data>
   <data name="Home.Title"><value>Hunting odds-flip anomalies</value></data>
@@ -272,6 +273,23 @@
   <data name="Export.Hub.Lede"><value>Export captured odds snapshots to an Excel workbook for any date range — no need to open a specific event first.</value></data>
   <data name="Export.Hub.Action"><value>Configure export</value></data>
   <data name="Export.Hub.FilenameHint"><value>Saved as Marathon_&lt;from&gt;_to_&lt;to&gt;.xlsx in the configured export directory.</value></data>
+  <data name="Health.Kicker"><value>Operations</value></data>
+  <data name="Health.Title"><value>Pipeline health</value></data>
+  <data name="Health.Lede"><value>Capture freshness, recent volumes, and worker status at a glance.</value></data>
+  <data name="Health.LastCapture"><value>Last capture</value></data>
+  <data name="Health.LastCapture.Never"><value>no captures yet</value></data>
+  <data name="Health.MinutesAgo"><value>{0} min ago</value></data>
+  <data name="Health.Stat.Snapshots"><value>Snapshots (24h)</value></data>
+  <data name="Health.Stat.Anomalies"><value>Anomalies (24h)</value></data>
+  <data name="Health.Stat.Events"><value>Events tracked</value></data>
+  <data name="Health.Stat.Sports"><value>Sports covered</value></data>
+  <data name="Health.Total"><value>{0} total</value></data>
+  <data name="Health.Workers"><value>Workers</value></data>
+  <data name="Health.Worker.Schedule"><value>Schedule poller</value></data>
+  <data name="Health.Worker.Live"><value>Live poller</value></data>
+  <data name="Health.Worker.Detection"><value>Anomaly detection</value></data>
+  <data name="Health.Worker.Results"><value>Results poller</value></data>
+  <data name="Health.Empty"><value>No data captured yet — enable the pollers in Settings.</value></data>
   <data name="Export.Error.MissingDates"><value>Pick a start and end date.</value></data>
   <data name="Export.Error.InvalidRange"><value>End date must be on or after the start date.</value></data>
   <data name="Export.Error.Failed"><value>Export failed.</value></data>

src/Marathon.UI/Resources/SharedResource.ru.resx

@@ -67,6 +67,7 @@
   <data name="Nav.Results"><value>Результаты</value></data>
   <data name="Nav.Settings"><value>Настройки</value></data>
   <data name="Nav.Export"><value>Экспорт</value></data>
+  <data name="Nav.Health"><value>Состояние</value></data>
 
   <!-- Home / Dashboard -->
   <data name="Home.Kicker"><value>Сводка</value></data>
@@ -285,6 +286,23 @@
   <data name="Export.Hub.Lede"><value>Экспорт собранных снимков коэффициентов в книгу Excel за любой диапазон дат — без необходимости открывать конкретное событие.</value></data>
   <data name="Export.Hub.Action"><value>Настроить экспорт</value></data>
   <data name="Export.Hub.FilenameHint"><value>Сохраняется как Marathon_&lt;от&gt;_to_&lt;до&gt;.xlsx в указанной папке экспорта.</value></data>
+  <data name="Health.Kicker"><value>Операции</value></data>
+  <data name="Health.Title"><value>Состояние конвейера</value></data>
+  <data name="Health.Lede"><value>Свежесть сбора, недавние объёмы и статус воркеров на одном экране.</value></data>
+  <data name="Health.LastCapture"><value>Последний снимок</value></data>
+  <data name="Health.LastCapture.Never"><value>снимков пока нет</value></data>
+  <data name="Health.MinutesAgo"><value>{0} мин назад</value></data>
+  <data name="Health.Stat.Snapshots"><value>Снимков (24ч)</value></data>
+  <data name="Health.Stat.Anomalies"><value>Аномалий (24ч)</value></data>
+  <data name="Health.Stat.Events"><value>Событий в работе</value></data>
+  <data name="Health.Stat.Sports"><value>Видов спорта</value></data>
+  <data name="Health.Total"><value>всего {0}</value></data>
+  <data name="Health.Workers"><value>Воркеры</value></data>
+  <data name="Health.Worker.Schedule"><value>Сбор расписания</value></data>
+  <data name="Health.Worker.Live"><value>Сбор лайва</value></data>
+  <data name="Health.Worker.Detection"><value>Детектор аномалий</value></data>
+  <data name="Health.Worker.Results"><value>Сбор результатов</value></data>
+  <data name="Health.Empty"><value>Данные ещё не собраны — включите сборщики в «Настройках».</value></data>
   <data name="Export.Error.MissingDates"><value>Выберите даты начала и конца.</value></data>
   <data name="Export.Error.InvalidRange"><value>Дата конца должна быть не раньше даты начала.</value></data>
   <data name="Export.Error.Failed"><value>Экспорт не удался.</value></data>

src/Marathon.UI/Services/IPipelineHealthService.cs

@@ -0,0 +1,37 @@
+namespace Marathon.UI.Services;
+
+/// <summary>
+/// Read-only operational health of the capture/detection pipeline, for the ops page:
+/// data freshness, recent vs total volumes, and which workers are enabled.
+/// </summary>
+public interface IPipelineHealthService
+{
+    Task<PipelineHealth> GetAsync(CancellationToken ct);
+}
+
+/// <summary>Snapshot of pipeline health. <see cref="LastSnapshotAt"/> drives the freshness pill.</summary>
+public sealed record PipelineHealth(
+    int EventsTracked,
+    int SportsCovered,
+    int SnapshotsLast24h,
+    int SnapshotsTotal,
+    int AnomaliesLast24h,
+    int AnomaliesTotal,
+    DateTimeOffset? LastSnapshotAt,
+    bool UpcomingPollerEnabled,
+    bool LivePollerEnabled,
+    bool ResultsPollerEnabled,
+    bool AnomalyDetectionEnabled)
+{
+    /// <summary>True once anything has been captured — gates the empty state.</summary>
+    public bool HasData => SnapshotsTotal > 0 || EventsTracked > 0;
+
+    /// <summary>Empty snapshot used as the initial render state before data loads.</summary>
+    public static PipelineHealth Empty { get; } = new(
+        EventsTracked: 0, SportsCovered: 0,
+        SnapshotsLast24h: 0, SnapshotsTotal: 0,
+        AnomaliesLast24h: 0, AnomaliesTotal: 0,
+        LastSnapshotAt: null,
+        UpcomingPollerEnabled: false, LivePollerEnabled: false,
+        ResultsPollerEnabled: false, AnomalyDetectionEnabled: false);
+}

src/Marathon.UI/Services/PipelineHealthService.cs

@@ -0,0 +1,58 @@
+using Marathon.Application.Abstractions;
+using Marathon.Domain.ValueObjects;
+using Microsoft.Extensions.Options;
+
+namespace Marathon.UI.Services;
+
+/// <summary>
+/// Repository-backed implementation of <see cref="IPipelineHealthService"/>. Composes
+/// server-side counts (no full-table materialisation) with the snapshot freshness and
+/// the worker-toggle state. Scoped — captures the per-circuit repository scope.
+/// </summary>
+public sealed class PipelineHealthService : IPipelineHealthService
+{
+    private readonly IEventRepository _events;
+    private readonly ISnapshotRepository _snapshots;
+    private readonly IAnomalyRepository _anomalies;
+    private readonly IOptionsMonitor<WorkerOptions> _workers;
+
+    public PipelineHealthService(
+        IEventRepository events,
+        ISnapshotRepository snapshots,
+        IAnomalyRepository anomalies,
+        IOptionsMonitor<WorkerOptions> workers)
+    {
+        _events = events ?? throw new ArgumentNullException(nameof(events));
+        _snapshots = snapshots ?? throw new ArgumentNullException(nameof(snapshots));
+        _anomalies = anomalies ?? throw new ArgumentNullException(nameof(anomalies));
+        _workers = workers ?? throw new ArgumentNullException(nameof(workers));
+    }
+
+    public async Task<PipelineHealth> GetAsync(CancellationToken ct)
+    {
+        var since24h = MoscowTime.Now.AddHours(-24);
+
+        var eventsTracked = await _events.CountAsync(ct).ConfigureAwait(false);
+        var sports = await _events.ListDistinctSportCodesAsync(ct).ConfigureAwait(false);
+        var snapshotsTotal = await _snapshots.CountSinceAsync(DateTimeOffset.MinValue, ct).ConfigureAwait(false);
+        var snapshots24h = await _snapshots.CountSinceAsync(since24h, ct).ConfigureAwait(false);
+        var anomaliesTotal = await _anomalies.CountSinceAsync(DateTimeOffset.MinValue, ct).ConfigureAwait(false);
+        var anomalies24h = await _anomalies.CountSinceAsync(since24h, ct).ConfigureAwait(false);
+        var lastSnapshotAt = await _snapshots.GetLatestCapturedAtAsync(ct).ConfigureAwait(false);
+
+        var w = _workers.CurrentValue;
+
+        return new PipelineHealth(
+            EventsTracked: eventsTracked,
+            SportsCovered: sports.Count,
+            SnapshotsLast24h: snapshots24h,
+            SnapshotsTotal: snapshotsTotal,
+            AnomaliesLast24h: anomalies24h,
+            AnomaliesTotal: anomaliesTotal,
+            LastSnapshotAt: lastSnapshotAt,
+            UpcomingPollerEnabled: w.UpcomingPollerEnabled,
+            LivePollerEnabled: w.LivePollerEnabled,
+            ResultsPollerEnabled: w.ResultsPollerEnabled,
+            AnomalyDetectionEnabled: w.AnomalyDetectionEnabled);
+    }
+}

src/Marathon.UI/Services/UiServicesExtensions.cs

@@ -62,6 +62,7 @@ public static class UiServicesExtensions
         services.AddScoped<IBetJournalService, BetJournalService>();
         services.AddScoped<IBacktestService, BacktestService>();
         services.AddScoped<IDashboardSummaryService, DashboardSummaryService>();
+        services.AddScoped<IPipelineHealthService, PipelineHealthService>();
 
         // Settings writer — file path is host-resolved.
         services.AddSingleton<ISettingsWriter>(_ => new JsonSettingsWriter(settingsLocalPath));

tests/Marathon.Infrastructure.Tests/Persistence/RoundTripTests.cs

@@ -366,6 +366,29 @@ public sealed class RoundTripTests : IDisposable
         many.Keys.Select(k => k.Value).Should().BeEquivalentTo(new[] { "Q1", "Q3" });
     }
 
+    [Fact]
+    public async Task Snapshot_GetLatestCapturedAt_ReturnsMostRecentOrNull()
+    {
+        // Empty store → null.
+        (await _snapshotRepo.GetLatestCapturedAtAsync()).Should().BeNull();
+
+        await _eventRepo.AddAsync(BuildEvent("L100"));
+        await _eventRepo.SaveChangesAsync();
+
+        var older = new DateTimeOffset(2026, 5, 1, 12, 0, 0, MoscowOffset);
+        var newer = new DateTimeOffset(2026, 5, 9, 18, 30, 0, MoscowOffset);
+        OddsSnapshot Snap(DateTimeOffset at) =>
+            new(new EventId("L100"), at, OddsSource.Live,
+                new List<Bet> { new(MatchScope.Instance, BetType.Win, Side.Side1, null, new OddsRate(1.90m)) });
+
+        await _snapshotRepo.AddAsync(Snap(older));
+        await _snapshotRepo.AddAsync(Snap(newer));
+        await _snapshotRepo.SaveChangesAsync();
+        _fixture.DbContext.ChangeTracker.Clear();
+
+        (await _snapshotRepo.GetLatestCapturedAtAsync()).Should().Be(newer);
+    }
+
     // ── Helpers ─────────────────────────────────────────────────────────────
 
     private static Event BuildEvent(string id, DateTimeOffset? scheduledAt = null) =>