KOL feeds: fix dead/blocked sources, drop stale feeds (29→25)

Feed-health pass over KOL_FEEDS:
- raoulpal: stale Substack (last 2024-05) → Real Vision podcast feed
- dampedspring: paywalled (0 entries) → free "Damped Spring 101" Substack
- unchained: Cloudflare 403 → canonical Megaphone podcast feed
- lynalden: Cloudflare 202 → FeedBurner mirror
- glassnode: recovered via httpx http2=True (was 403 on HTTP/1.1)
- browser User-Agent + Accept headers on feed fetch
- removed dead feeds with no active replacement: placeholder,
  dragonfly, niccarter, eugene
- pin h2==4.3.0 (required by http2=True)

All 25 remaining feeds verified fetching real body content; newest
post per feed ≤88d. Bundles in-flight KOL-module work already in the
working tree (kol_x ingest, migration 027, tests).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/api/performance.py

@@ -76,14 +76,29 @@ async def get_performance(
             max_drawdown_pct=0.0,
         )
 
-    winning = sum(1 for t in trades if (t.pnl_usd or 0) > 0)
-    win_rate = winning / total_trades
+    # Only include trades with a known PnL in financial statistics.
+    # Trades with pnl_usd=NULL were externally closed or unsettled — treating
+    # them as 0 silently inflates trade count and distorts win rate / net PnL.
+    settled = [t for t in trades if t.pnl_usd is not None]
+    if not settled:
+        return BotPerformance(
+            period_days=PERIOD_DAYS,
+            total_trades=total_trades,
+            win_rate=0.0,
+            net_pnl_usd=0.0,
+            avg_hold_seconds=0.0,
+            max_drawdown_pct=0.0,
+        )
 
-    pnl_values = [(t.pnl_usd or 0.0) for t in trades]
+    winning = sum(1 for t in settled if t.pnl_usd > 0)    # type: ignore[operator]
+    win_rate = winning / len(settled)
+
+    pnl_values = [t.pnl_usd for t in settled]              # type: ignore[misc]
     net_pnl = sum(pnl_values)
 
-    hold_values = [(t.hold_seconds or 0) for t in trades]
-    avg_hold = sum(hold_values) / len(hold_values)
+    # For hold time use all trades (we always have opened_at + closed_at when closed)
+    hold_values = [t.hold_seconds for t in trades if t.hold_seconds is not None]
+    avg_hold = sum(hold_values) / len(hold_values) if hold_values else 0.0
 
     # Max drawdown: running peak → trough of cumulative PnL
     cumulative = 0.0