debug: Add comprehensive logging to Position Manager checkTradeConditions (Bug #77 recurrence)

CRITICAL INVESTIGATION (Dec 15, 2025):
- Monitoring loop runs every 2s: "🔍 Price check: SOL-PERP @ $124.47 (1 trades)" ✓
- But NO condition checks execute: No TP1/TP2/SL detection, no executeExit calls ❌
- Impact: ,000+ losses - 96% data loss ($32.98 actual vs $1.23 recorded)

Added debug logging:
- STARTCHK: Function entry (price, entry, check count)
- DRIFT: Position size and existence from Drift API
- AGE: Trade age in seconds vs 30s threshold

Purpose: Identify WHERE checkTradeConditions() returns early before reaching condition checks at line 1497+

Hypothesis: Either Drift returns size=0 OR trade age check fails, causing early return at line 711

lib/trading/position-manager.ts

@@ -688,6 +688,9 @@ export class PositionManager {
     trade.lastUpdateTime = Date.now()
     trade.priceCheckCount++
     
+    // BUG #77 RECURRENCE FIX (Dec 15, 2025): CRITICAL debugging to find why condition checks never execute
+    console.log(`🔍 STARTCHK: ${trade.symbol} @ $${currentPrice.toFixed(2)} | Entry: $${trade.entryPrice.toFixed(2)} | Checks: ${trade.priceCheckCount}`)
+    
     // CRITICAL: First check if on-chain position still exists
     // (may have been closed by TP/SL orders without us knowing)
     try {
@@ -700,8 +703,11 @@ export class PositionManager {
       const marketConfig = getMarketConfig(trade.symbol)
       const position = await driftService.getPosition(marketConfig.driftMarketIndex)
       
+      console.log(`🔍 DRIFT: Position ${trade.symbol} | size=${position?.size || 'null'} | exists=${position !== null}`)
+      
       // Calculate trade age in seconds
       const tradeAgeSeconds = (Date.now() - trade.entryTime) / 1000
+      console.log(`🔍 AGE: ${trade.symbol} age=${tradeAgeSeconds.toFixed(1)}s | threshold=30s`)
       
       if (position === null || position.size === 0) {
         // IMPORTANT: Skip "external closure" detection for NEW trades (<30 seconds old)