feat(my-bets): personal bet journal with CLV tracking

Adds a manual bet-tracking journal that turns the analyzer into an actual
bet tracker. Users record wagers; the journal auto-grades them when event
results land and computes per-bet Closing-Line-Value against the latest
pre-match snapshot — the strongest long-run indicator of betting skill.

Domain:
- PlacedBet entity (reuses Bet vocabulary for Scope/Type/Side/Value/Rate)
  with stake, placed-at, outcome, and notes. Derived GrossReturn / NetProfit.
- BetOutcome enum (Pending / Won / Lost / Void).
- BetOutcomeResolver: pure function grading any Match-scope bet against an
  EventResult. Handles 1X2, draws, handicap (incl. push), and totals.
  Period-scope bets stay manual since EventResult only carries full-time.

Application:
- IPlacedBetRepository abstraction.
- ClosingLineValueCalculator: pure CLV math (implied-probability delta) +
  snapshot-matching predicate by Scope/Type/Side/Value.
- BetJournalReport + BetJournalStats records.
- Four use cases: Record / ResolvePending / BuildReport / Delete.
- New ISnapshotRepository.GetLatestPreMatchAsync pushes the closing-line
  pick into a single SQLite query rather than materialising the 30-day
  window in memory per event.
- ROI turnover excludes Void stakes — pushes are not real turnover and
  including them would dilute the user's edge.

Infrastructure:
- PlacedBetEntity / Configuration / Repository / Mapping helpers.
- 20260516 migration adding the PlacedBets table with EventCode and
  Outcome indices. Intentionally NO foreign key to Events — the journal
  is user data and must survive snapshot-retention pruning. Covered by an
  explicit round-trip test.

UI:
- Pages/MyBets/Journal.razor: hero header, 4-card KPI strip (ROI / strike
  rate / avg CLV / net profit, tinted by tone), inline add-bet form with
  the same invariants as the Bet record, drill-down table with per-row
  outcome pills, CLV percentage-points column, P&L, notes underline, and
  inline-confirm delete. RU + EN i18n.
- Nav entry under Analysis.

Tests: +55 across Domain / Application / Infrastructure (resolver math
including handicap push and total push boundaries, PlacedBet invariants
and derived properties, CLV math + null-handling, four use cases under
NSubstitute, EF round-trip including survives-event-deletion). All 379
tests pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

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

@@ -0,0 +1,87 @@
+using Marathon.Application.Abstractions;
+using Marathon.Application.Storage;
+using Marathon.Domain.Entities;
+using Marathon.Domain.Enums;
+using Marathon.Domain.ValueObjects;
+using Microsoft.EntityFrameworkCore;
+
+namespace Marathon.Infrastructure.Persistence.Repositories;
+
+internal sealed class PlacedBetRepository : IPlacedBetRepository
+{
+    private readonly MarathonDbContext _db;
+
+    public PlacedBetRepository(MarathonDbContext db) => _db = db;
+
+    public async Task<PlacedBet?> GetAsync(Guid key, CancellationToken ct = default)
+    {
+        var idStr = key.ToString();
+        // AsNoTracking so callers can re-map and UpdateAsync without tripping
+        // EF's "another instance with the same key is already tracked" guard.
+        var entity = await _db.PlacedBets.AsNoTracking()
+            .FirstOrDefaultAsync(b => b.Id == idStr, ct);
+        return entity is null ? null : Mapping.ToDomain(entity);
+    }
+
+    public async Task<IReadOnlyList<PlacedBet>> ListAsync(CancellationToken ct = default)
+    {
+        var entities = await _db.PlacedBets.AsNoTracking().ToListAsync(ct);
+        return entities.Select(Mapping.ToDomain).ToList().AsReadOnly();
+    }
+
+    public async Task<IReadOnlyList<PlacedBet>> ListByOutcomeAsync(BetOutcome outcome, CancellationToken ct = default)
+    {
+        var outcomeInt = (int)outcome;
+        var entities = await _db.PlacedBets.AsNoTracking()
+            .Where(b => b.Outcome == outcomeInt)
+            .ToListAsync(ct);
+        return entities.Select(Mapping.ToDomain).ToList().AsReadOnly();
+    }
+
+    public async Task<IReadOnlyList<PlacedBet>> ListByDateRangeAsync(DateRange range, CancellationToken ct = default)
+    {
+        // PlacedAt is stored as ISO 8601 TEXT — same lexical-equals-chronological ordering
+        // trick used in EventRepository.ListByDateRangeAsync.
+        var fromStr = range.From.ToString("O");
+        var toStr = range.To.ToString("O");
+
+        var entities = await _db.PlacedBets.AsNoTracking()
+            .Where(b => b.PlacedAt.CompareTo(fromStr) >= 0
+                     && b.PlacedAt.CompareTo(toStr) <= 0)
+            .ToListAsync(ct);
+
+        return entities.Select(Mapping.ToDomain).ToList().AsReadOnly();
+    }
+
+    public async Task<IReadOnlyList<PlacedBet>> ListByEventAsync(EventId eventId, CancellationToken ct = default)
+    {
+        var entities = await _db.PlacedBets.AsNoTracking()
+            .Where(b => b.EventCode == eventId.Value)
+            .ToListAsync(ct);
+        return entities.Select(Mapping.ToDomain).ToList().AsReadOnly();
+    }
+
+    public async Task AddAsync(PlacedBet entity, CancellationToken ct = default)
+    {
+        var efEntity = Mapping.ToEntity(entity);
+        await _db.PlacedBets.AddAsync(efEntity, ct);
+    }
+
+    public Task UpdateAsync(PlacedBet entity, CancellationToken ct = default)
+    {
+        var efEntity = Mapping.ToEntity(entity);
+        _db.PlacedBets.Update(efEntity);
+        return Task.CompletedTask;
+    }
+
+    public async Task DeleteAsync(Guid key, CancellationToken ct = default)
+    {
+        var idStr = key.ToString();
+        var entity = await _db.PlacedBets.FirstOrDefaultAsync(b => b.Id == idStr, ct);
+        if (entity is not null)
+            _db.PlacedBets.Remove(entity);
+    }
+
+    public async Task SaveChangesAsync(CancellationToken ct = default) =>
+        await _db.SaveChangesAsync(ct);
+}