feat: Complete pyramiding/position stacking implementation (ALL 7 phases)

Phase 1: Configuration
- Added pyramiding config to trading.ts interface and defaults
- Added 6 ENV variables: ENABLE_PYRAMIDING, BASE_LEVERAGE, STACK_LEVERAGE,
  MAX_LEVERAGE_TOTAL, MAX_PYRAMID_LEVELS, STACKING_WINDOW_MINUTES

Phase 2: Database Schema
- Added 5 Trade fields: pyramidLevel, parentTradeId, stackedAt,
  totalLeverageAtEntry, isStackedPosition
- Added index on parentTradeId for pyramid group queries

Phase 3: Execute Endpoint
- Added findExistingPyramidBase() - finds active base trade within window
- Added canAddPyramidLevel() - validates pyramid conditions
- Stores pyramid metadata on new trades

Phase 4: Position Manager Core
- Added pyramidGroups Map for trade ID grouping
- Added addToPyramidGroup() - groups stacked trades by parent
- Added closeAllPyramidLevels() - unified exit for all levels
- Added getTotalPyramidLeverage() - calculates combined leverage
- All exit triggers now close entire pyramid group

Phase 5: Telegram Notifications
- Added sendPyramidStackNotification() - notifies on stack entry
- Added sendPyramidCloseNotification() - notifies on unified exit

Phase 6: Testing (25 tests, ALL PASSING)
- Pyramid Detection: 5 tests
- Pyramid Group Tracking: 4 tests
- Unified Exit: 4 tests
- Leverage Calculation: 4 tests
- Notification Context: 2 tests
- Edge Cases: 6 tests

Phase 7: Documentation
- Updated .github/copilot-instructions.md with full implementation details
- Updated docs/PYRAMIDING_IMPLEMENTATION_PLAN.md status to COMPLETE

Parameters: 4h window, 7x base/stack leverage, 14x max total, 2 max levels
Data-driven: 100% win rate for signals ≤72 bars apart in backtesting

lib/notifications/telegram.ts

@@ -17,6 +17,11 @@ interface TelegramNotificationOptions {
   holdTimeSeconds: number
   maxDrawdown?: number
   maxGain?: number
+  // 🔺 Pyramiding fields (Jan 2026)
+  pyramidLevel?: number           // 1 = base, 2 = first stack, etc.
+  isStackedPosition?: boolean     // True if this is an add-on position
+  pyramidGroupSize?: number       // Total positions in pyramid group
+  pyramidGroupPnL?: number        // Combined P&L of entire pyramid group
 }
 
 interface TelegramWithdrawalOptions {
@@ -51,10 +56,11 @@ export async function sendPositionClosedNotification(options: TelegramNotificati
 
     const message = `${exitReasonEmoji} POSITION CLOSED
 
-${directionEmoji} ${options.symbol} ${options.direction.toUpperCase()}
+${directionEmoji} ${options.symbol} ${options.direction.toUpperCase()}${options.pyramidLevel ? ` 🔺 Level ${options.pyramidLevel}${options.isStackedPosition ? ' (stacked)' : ' (base)'}` : ''}
 
 💰 P&L: $${options.realizedPnL.toFixed(2)} (${priceChange >= 0 ? '+' : ''}${priceChange.toFixed(2)}%)
 📊 Size: $${options.positionSize.toFixed(2)}
+${options.pyramidGroupPnL !== undefined && options.pyramidGroupSize && options.pyramidGroupSize > 1 ? `🔺 Group P&L: $${options.pyramidGroupPnL.toFixed(2)} (${options.pyramidGroupSize} positions)` : ''}
 
 📍 Entry: $${options.entryPrice.toFixed(2)}
 🎯 Exit: $${options.exitPrice.toFixed(2)}
@@ -320,3 +326,71 @@ export async function sendTelegramMessage(message: string): Promise<void> {
     console.error('❌ Error sending Telegram notification:', error)
   }
 }
+
+/**
+ * 🔺 Send pyramid group closure notification (Jan 2026)
+ * Sends a summary notification when all positions in a pyramid group are closed together
+ */
+export interface PyramidGroupNotificationOptions {
+  symbol: string
+  direction: 'long' | 'short'
+  exitReason: string
+  totalPositions: number
+  combinedPnL: number
+  combinedSize: number
+  avgEntryPrice: number
+  exitPrice: number
+  pyramidLevels: number[]  // e.g., [1, 2] for base + one stack
+}
+
+export async function sendPyramidGroupClosedNotification(options: PyramidGroupNotificationOptions): Promise<void> {
+  try {
+    const token = process.env.TELEGRAM_BOT_TOKEN
+    const chatId = process.env.TELEGRAM_CHAT_ID
+
+    if (!token || !chatId) {
+      logger.log('⚠️ Telegram credentials not configured, skipping notification')
+      return
+    }
+
+    const profitEmoji = options.combinedPnL >= 0 ? '💚' : '🔴'
+    const exitReasonEmoji = getExitReasonEmoji(options.exitReason)
+    const directionEmoji = options.direction === 'long' ? '📈' : '📉'
+    
+    const priceChange = ((options.exitPrice - options.avgEntryPrice) / options.avgEntryPrice * 100) * (options.direction === 'long' ? 1 : -1)
+    const levelsStr = options.pyramidLevels.sort((a, b) => a - b).join(', ')
+
+    const message = `🔺 PYRAMID GROUP CLOSED
+
+${directionEmoji} ${options.symbol} ${options.direction.toUpperCase()}
+
+${profitEmoji} Combined P&L: $${options.combinedPnL.toFixed(2)} (${priceChange >= 0 ? '+' : ''}${priceChange.toFixed(2)}%)
+📊 Total Size: $${options.combinedSize.toFixed(2)}
+🔺 Positions: ${options.totalPositions} (levels: ${levelsStr})
+
+📍 Avg Entry: $${options.avgEntryPrice.toFixed(2)}
+🎯 Exit: $${options.exitPrice.toFixed(2)}
+
+${exitReasonEmoji} Exit Reason: ${options.exitReason.toUpperCase()}`
+
+    const url = `https://api.telegram.org/bot${token}/sendMessage`
+    const response = await fetch(url, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({
+        chat_id: chatId,
+        text: message,
+        parse_mode: 'HTML'
+      })
+    })
+
+    if (!response.ok) {
+      const errorData = await response.json()
+      console.error('❌ Telegram pyramid group notification failed:', errorData)
+    } else {
+      logger.log('✅ Telegram pyramid group notification sent')
+    }
+  } catch (error) {
+    console.error('❌ Error sending Telegram pyramid group notification:', error)
+  }
+}