Add v7-momentum indicator (experimental, disabled)

- Created momentum scalper indicator for catching rapid price acceleration
- ROC-based detection: 2.0% threshold over 5 bars
- Volume confirmation: 2.0x spike (checks last 3 bars)
- ADX filter: Requires 12+ minimum directional movement
- Anti-chop filter: Blocks signals in dead markets
- Debug table: Real-time metric display for troubleshooting

Status: Functional but signal quality inferior to v6 HalfTrend
Decision: Shelved for now, continue with proven v6 strategy
File: docs/guides/MOMENTUM_INDICATOR_V1.pine (239 lines)

Lessons learned:
- Momentum indicators inherently noisy (40-50% WR expected)
- Signals either too early (false breakouts) or too late (miss move)
- Volume spike timing issue: Often lags price move by 1-2 bars
- Better to optimize proven strategy than add complexity

Related: Position Manager duplicate update bug fixed (awaiting verification)

.github/copilot-instructions.md

@@ -888,6 +888,36 @@ trade.realizedPnL += actualRealizedPnL  // NOT: result.realizedPnL from SDK
     - **v5:** Buy/Sell Signal strategy (pre-Nov 12)
     - **v6:** HalfTrend + BarColor strategy (Nov 12+)
     - Used for performance comparison between strategies
+
+26. **External closure duplicate updates bug (CRITICAL - Fixed Nov 12, 2025):**
+    - **Symptom:** Trades showing 7-8x larger losses than actual ($58 loss when Drift shows $7 loss)
+    - **Root Cause:** Position Manager monitoring loop re-processes external closures multiple times before trade removed from activeTrades Map
+    - **Bug sequence:**
+      1. Trade closed externally (on-chain SL order fills at -$7.98)
+      2. Position Manager detects closure: `position === null`
+      3. Calculates P&L and calls `updateTradeExit()` → -$7.50 in DB
+      4. **BUT:** Trade still in `activeTrades` Map (removal happens after DB update)
+      5. Next monitoring loop (2s later) detects closure AGAIN
+      6. Accumulates P&L: `previouslyRealized (-$7.50) + runnerRealized (-$7.50) = -$15.00`
+      7. Updates database AGAIN → -$15.00 in DB
+      8. Repeats 8 times → final -$58.43 (8× the actual loss)
+    - **Fix:** Remove trade from `activeTrades` Map BEFORE database update:
+    ```typescript
+    // BEFORE (BROKEN):
+    await updateTradeExit({ ... })
+    await this.removeTrade(trade.id)  // Too late! Loop already ran again
+    
+    // AFTER (FIXED):
+    this.activeTrades.delete(trade.id)  // Remove FIRST
+    await updateTradeExit({ ... })      // Then update DB
+    if (this.activeTrades.size === 0) {
+      this.stopMonitoring()
+    }
+    ```
+    - **Impact:** Without this fix, every external closure is recorded 5-8 times with compounding P&L
+    - **Root cause:** Async timing issue - `removeTrade()` is async but monitoring loop continues synchronously
+    - **Evidence:** Logs showed 8 consecutive "External closure recorded" messages with increasing P&L
+    - **Line:** `lib/trading/position-manager.ts` line 493 (external closure detection block)
     - Must update `CreateTradeParams` interface when adding new database fields (see pitfall #21)
     - Analytics endpoint `/api/analytics/version-comparison` compares v5 vs v6 performance