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.Application/Betting/BetJournalReport.cs

@@ -0,0 +1,92 @@
+using Marathon.Domain.Entities;
+using Marathon.Domain.Enums;
+
+namespace Marathon.Application.Betting;
+
+/// <summary>
+/// Aggregate report on the user's bet-tracking journal — totals, P&amp;L, and
+/// per-bet CLV. Consumed by the Journal page; built by
+/// <see cref="UseCases.BuildBetJournalReportUseCase"/>.
+/// </summary>
+/// <param name="Stats">Roll-up of stake / profit / hit rate / CLV across all bets in scope.</param>
+/// <param name="Bets">
+/// Every bet paired with its computed CLV (null when no closing snapshot was
+/// available). Ordered most-recent <see cref="PlacedBet.PlacedAt"/> first.
+/// </param>
+public sealed record BetJournalReport(
+    BetJournalStats Stats,
+    IReadOnlyList<BetJournalRow> Bets);
+
+/// <summary>
+/// One row in the journal — a domain <see cref="PlacedBet"/> plus the CLV
+/// computed against the closing pre-match snapshot.
+/// </summary>
+/// <param name="Bet">The domain bet exactly as persisted.</param>
+/// <param name="ClvProbabilityDelta">
+/// Closing-line value as an implied-probability delta in roughly [-1, 1].
+/// Positive means the user took a better price than the closing line; null
+/// when no matching bet existed in the closing snapshot.
+/// </param>
+public sealed record BetJournalRow(
+    PlacedBet Bet,
+    decimal? ClvProbabilityDelta);
+
+/// <summary>
+/// Aggregate statistics across a set of <see cref="PlacedBet"/>.
+/// All money values share the user's currency — the domain does not encode one.
+/// </summary>
+/// <param name="TotalBets">Every bet in scope, regardless of outcome.</param>
+/// <param name="PendingCount">Bets still awaiting settlement.</param>
+/// <param name="WonCount">Settled wins.</param>
+/// <param name="LostCount">Settled losses.</param>
+/// <param name="VoidCount">Settled pushes / void grades.</param>
+/// <param name="TotalStaked">
+/// Turnover that contributes to ROI: sum of <see cref="PlacedBet.Stake"/> across
+/// <b>Won and Lost</b> bets only. Void (push) and Pending bets are excluded — a
+/// returned stake is not real turnover and counting it would dilute ROI.
+/// </param>
+/// <param name="TotalReturned">
+/// Sum of <see cref="PlacedBet.GrossReturn"/> across the same Won + Lost subset
+/// that feeds <see cref="TotalStaked"/>.
+/// </param>
+/// <param name="NetProfit"><c>TotalReturned − TotalStaked</c>.</param>
+/// <param name="RoiPercent">
+/// <c>NetProfit / TotalStaked × 100</c>. Null when no bets have resolved yet.
+/// </param>
+/// <param name="StrikeRatePercent">
+/// <c>WonCount / (WonCount + LostCount) × 100</c> — excludes voids and pendings.
+/// Null when no settled win/loss exists yet.
+/// </param>
+/// <param name="AverageClvProbabilityDelta">
+/// Mean CLV across bets where CLV was computable. Null when no comparable
+/// closing snapshot was available for any bet.
+/// </param>
+public sealed record BetJournalStats(
+    int TotalBets,
+    int PendingCount,
+    int WonCount,
+    int LostCount,
+    int VoidCount,
+    decimal TotalStaked,
+    decimal TotalReturned,
+    decimal NetProfit,
+    decimal? RoiPercent,
+    decimal? StrikeRatePercent,
+    decimal? AverageClvProbabilityDelta)
+{
+    /// <summary>Convenience: WonCount + LostCount + VoidCount.</summary>
+    public int ResolvedCount => WonCount + LostCount + VoidCount;
+
+    public static BetJournalStats Empty { get; } = new(
+        TotalBets: 0,
+        PendingCount: 0,
+        WonCount: 0,
+        LostCount: 0,
+        VoidCount: 0,
+        TotalStaked: 0m,
+        TotalReturned: 0m,
+        NetProfit: 0m,
+        RoiPercent: null,
+        StrikeRatePercent: null,
+        AverageClvProbabilityDelta: null);
+}