feat: Add comprehensive database save protection system

INVESTIGATION RESULT: No database failure occurred - trade was saved correctly.
However, implemented 5-layer protection against future failures:

1. Persistent File Logger (lib/utils/persistent-logger.ts)
   - Survives container restarts
   - Logs to /app/logs/errors.log
   - Daily rotation, 30-day retention

2. Database Save Retry Logic (lib/database/trades.ts)
   - 3 retry attempts with exponential backoff (1s, 2s, 4s)
   - Immediate verification query after each create
   - Persistent logging of all attempts

3. Orphan Position Detection (lib/startup/init-position-manager.ts)
   - Runs on every container startup
   - Queries Drift for positions without database records
   - Creates retroactive Trade records
   - Sends Telegram alerts
   - Restores Position Manager monitoring

4. Critical Logging (app/api/trading/execute/route.ts)
   - Database failures logged with full trade details
   - Stack traces preserved for debugging

5. Infrastructure (logs directory + Docker volume)
   - Mounted at /home/icke/traderv4/logs
   - Configured in docker-compose.yml

Trade from Nov 21 00:40:14 CET:
- Found in database: cmi82qg590001tn079c3qpw4r
- SHORT SOL-PERP 33.69 → 34.67 SL
- P&L: -9.17
- Closed at 01:17:03 CET (37 minutes duration)
- No database failure occurred

Future Protection:
- Retry logic catches transient failures
- Verification prevents silent failures
- Orphan detection catches anything missed
- Persistent logs enable post-mortem analysis
- System now bulletproof for 16 → 00k journey

app/api/trading/execute/route.ts

@@ -15,6 +15,7 @@ import { createTrade, updateTradeExit } from '@/lib/database/trades'
 import { scoreSignalQuality } from '@/lib/trading/signal-quality'
 import { getMarketDataCache } from '@/lib/trading/market-data-cache'
 import { getPythPriceMonitor } from '@/lib/pyth/price-monitor'
+import { logCriticalError, logTradeExecution } from '@/lib/utils/persistent-logger'
 
 export interface ExecuteTradeRequest {
   symbol: string // TradingView symbol (e.g., 'SOLUSDT')
@@ -803,11 +804,40 @@ export async function POST(request: NextRequest): Promise<NextResponse<ExecuteTr
       console.log('🔍 DEBUG: createTrade() completed successfully')
       console.log(`💾 Trade saved with quality score: ${qualityResult.score}/100`)
       console.log(`📊 Quality reasons: ${qualityResult.reasons.join(', ')}`)
+      
+      // Log successful trade execution to persistent file
+      logTradeExecution(true, {
+        symbol: driftSymbol,
+        direction: body.direction,
+        entryPrice,
+        positionSize: positionSizeUSD,
+        transactionSignature: openResult.transactionSignature
+      })
     } catch (dbError) {
       console.error('❌ CRITICAL: Failed to save trade to database:', dbError)
       console.error('   Position is OPEN on Drift but NOT tracked!')
       console.error('   Manual intervention required - close position immediately')
       
+      // Log to persistent file (survives container restarts)
+      logCriticalError('Database save failed during trade execution', {
+        symbol: driftSymbol,
+        direction: body.direction,
+        entryPrice,
+        positionSize: positionSizeUSD,
+        transactionSignature: openResult.transactionSignature,
+        error: dbError instanceof Error ? dbError.message : String(dbError),
+        stack: dbError instanceof Error ? dbError.stack : undefined
+      })
+      
+      logTradeExecution(false, {
+        symbol: driftSymbol,
+        direction: body.direction,
+        entryPrice,
+        positionSize: positionSizeUSD,
+        transactionSignature: openResult.transactionSignature,
+        error: dbError instanceof Error ? dbError.message : 'Database save failed'
+      })
+      
       // CRITICAL: If database save fails, we MUST NOT add to Position Manager
       // Return error to user so they know to close manually
       return NextResponse.json(