Fix embedded-server endpoint drift, add Recalculate All Traders button

- Shared ApiConfiguration.MapPredictalyticsEndpoints() used by both the
  standalone API and the embedded WinForms Kestrel server: the embedded
  host was missing /api/watchlist and /api/dev (empty watchlist page),
  the standalone host was missing /api/search.
- New Development menu action "Recalculate All Traders": backfills
  ResolutionOutcome from snapped outcome prices, wipes derived analytics
  (snapshots, category stats, rebuildable positions), zeroes aggregates
  and marks every trader for re-analysis. Raw trades untouched.
- Static files now served with Cache-Control: no-cache in both hosts,
  plus ?v= cache-buster on app.js/style.css (stale browser JS masked
  earlier UI fixes).
- Watchlist hardened: endpoint null-safe, real Analytics.CopytradingScore,
  Platform field; repository includes Trader.Analytics; page shows a
  visible error row instead of staying silently blank.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/Predictalytics.Infrastructure/Data/Repositories/WatchlistRepository.cs

@@ -10,7 +10,10 @@ public class WatchlistRepository : IWatchlistRepository
     public WatchlistRepository(AppDbContext db) => _db = db;
 
     public async Task<IReadOnlyList<WatchlistEntry>> GetAllAsync(CancellationToken ct = default)
-        => await _db.WatchlistEntries.Include(w => w.Trader).ToListAsync(ct);
+        => await _db.WatchlistEntries
+            .Include(w => w.Trader)
+                .ThenInclude(t => t.Analytics)
+            .ToListAsync(ct);
 
     public async Task<WatchlistEntry?> GetByTraderIdAsync(int traderId, CancellationToken ct = default)
         => await _db.WatchlistEntries.FirstOrDefaultAsync(w => w.TraderId == traderId, ct);