fix: Add retry logic to exit order placement (TP/SL)

CRITICAL FIX: Exit orders failed without retry on 429 rate limits

Root Cause:
- placeExitOrders() placed TP1/TP2/SL orders directly without retry wrapper
- cancelAllOrders() HAD retry logic (8s → 16s → 32s progression)
- Rate limit errors during exit order placement = unprotected positions
- If container crashes after opening, no TP/SL orders on-chain

Fix Applied:
- Wrapped ALL order placements in retryWithBackoff():
  * TP1 limit order (line ~310)
  * TP2 limit order (line ~334)
  * Soft stop trigger-limit (dual stop system)
  * Hard stop trigger-market (dual stop system)
  * Single stop trigger-limit
  * Single stop trigger-market (default)

Retry Behavior:
- Base delay: 8 seconds (was 5s, increased Nov 14)
- Progression: 8s → 16s → 32s (max 3 retries)
- Logs rate_limit_recovered to database on success
- Logs rate_limit_exhausted on max retries exceeded

Impact:
- Exit orders now retry up to 3x on 429 errors (56 seconds total wait)
- Positions protected even during RPC rate limit spikes
- Reduces need for immediate Helius upgrade
- Database analytics track retry success/failure

Files: lib/drift/orders.ts (6 placePerpOrder calls wrapped)

Note: cancelAllOrders() already had retry logic - this completes coverage

lib/drift/orders.ts

@@ -307,7 +307,9 @@ export async function placeExitOrders(options: PlaceExitOrdersOptions): Promise<
         }
 
         console.log('🚧 Placing TP1 limit order (reduce-only)...')
-        const sig = await (driftClient as any).placePerpOrder(orderParams)
+        const sig = await retryWithBackoff(async () => 
+          await (driftClient as any).placePerpOrder(orderParams)
+        )
         console.log('✅ TP1 order placed:', sig)
         signatures.push(sig)
       } else {
@@ -329,7 +331,9 @@ export async function placeExitOrders(options: PlaceExitOrdersOptions): Promise<
         }
 
         console.log('🚧 Placing TP2 limit order (reduce-only)...')
-        const sig = await (driftClient as any).placePerpOrder(orderParams)
+        const sig = await retryWithBackoff(async () =>
+          await (driftClient as any).placePerpOrder(orderParams)
+        )
         console.log('✅ TP2 order placed:', sig)
         signatures.push(sig)
       } else {
@@ -377,7 +381,9 @@ export async function placeExitOrders(options: PlaceExitOrdersOptions): Promise<
         console.log(`      Limit: $${(options.softStopPrice * softStopMultiplier).toFixed(4)}`)
         console.log(`      Purpose: Avoid false breakouts/wicks`)
         
-        const softStopSig = await (driftClient as any).placePerpOrder(softStopParams)
+        const softStopSig = await retryWithBackoff(async () =>
+          await (driftClient as any).placePerpOrder(softStopParams)
+        )
         console.log(`      ✅ Soft stop placed: ${softStopSig}`)
         signatures.push(softStopSig)
         
@@ -398,7 +404,9 @@ export async function placeExitOrders(options: PlaceExitOrdersOptions): Promise<
         console.log(`      Trigger: $${options.hardStopPrice.toFixed(4)}`)
         console.log(`      Purpose: Guaranteed exit if soft stop doesn't fill`)
         
-        const hardStopSig = await (driftClient as any).placePerpOrder(hardStopParams)
+        const hardStopSig = await retryWithBackoff(async () =>
+          await (driftClient as any).placePerpOrder(hardStopParams)
+        )
         console.log(`      ✅ Hard stop placed: ${hardStopSig}`)
         signatures.push(hardStopSig)
         
@@ -433,7 +441,9 @@ export async function placeExitOrders(options: PlaceExitOrdersOptions): Promise<
           console.log(`   Limit: $${(options.stopLossPrice * limitPriceMultiplier).toFixed(4)}`)
           console.log(`   ⚠️  May not fill during fast moves - use for liquid markets only!`)
           
-          const sig = await (driftClient as any).placePerpOrder(orderParams)
+          const sig = await retryWithBackoff(async () =>
+            await (driftClient as any).placePerpOrder(orderParams)
+          )
           console.log('✅ SL trigger-limit order placed:', sig)
           signatures.push(sig)
         } else {
@@ -454,7 +464,9 @@ export async function placeExitOrders(options: PlaceExitOrdersOptions): Promise<
           console.log(`   Trigger: ${options.direction === 'long' ? 'BELOW' : 'ABOVE'} $${options.stopLossPrice.toFixed(4)}`)
           console.log(`   ✅ Will execute at market price when triggered (may slip but WILL fill)`)
           
-          const sig = await (driftClient as any).placePerpOrder(orderParams)
+          const sig = await retryWithBackoff(async () =>
+            await (driftClient as any).placePerpOrder(orderParams)
+          )
           console.log('✅ SL trigger-market order placed:', sig)
           signatures.push(sig)
         }