feat(notify): Telegram alerts on trade open and close

New module bot/notify/telegram.py — httpx async, fire-and-forget via
asyncio.create_task, swallows all errors so notifications never affect
trade execution.

Three alert types:
  📈/📉 TRADE ABIERTO  — direction, size, edge_net (in execute())
  ✅/❌  GANADO/PERDIDO — approx PnL (in close_position())
  🔒    LEGACY CLOSE   — recovered capital + reason (in close_legacy_position())

close_position() and close_legacy_position() gain an optional question=""
param so the message shows the market name instead of market_id.
bot/main.py updated to pass question= to close_legacy_position().

Credentials (TELEGRAM_BOT_TOKEN, TELEGRAM_CHAT_ID) read from env vars
injected via bot-secrets k8s secret.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bot/executor/paper.py

@@ -4,6 +4,7 @@ Paper Trading Executor — simulates order execution without real money.
 Simulates realistic slippage and fees to get accurate paper P&L.
 All trades are logged to PostgreSQL for metrics analysis.
 """
+import asyncio
 import logging
 import uuid
 from dataclasses import dataclass, field
@@ -12,6 +13,7 @@ from typing import Optional
 
 from bot.risk.manager import Order, Portfolio
 from bot.data.db import Database
+from bot.notify import telegram
 
 log = logging.getLogger(__name__)
 
@@ -183,9 +185,13 @@ class PaperExecutor:
         # Persist to DB
         await self._db.save_trade(trade)
 
+        asyncio.create_task(
+            telegram.trade_opened(trade.question, trade.direction, trade.size_usdc, trade.edge_net)
+        )
+
         return trade
 
-    async def close_legacy_position(self, market_id: str, reason: str) -> float:
+    async def close_legacy_position(self, market_id: str, reason: str, question: str = "") -> float:
         """
         Close a paper position flagged by the legacy scan.
 
@@ -200,9 +206,12 @@ class PaperExecutor:
             "LEGACY_CLOSE market=%s | returned $%.2f to cash | %s",
             market_id, cost, reason[:80],
         )
+        asyncio.create_task(
+            telegram.trade_legacy_closed(question or market_id, cost, reason)
+        )
         return cost
 
-    async def close_position(self, market_id: str, resolution: float) -> Optional[float]:
+    async def close_position(self, market_id: str, resolution: float, question: str = "") -> Optional[float]:
         """Close a paper position after market resolution.
 
         resolution: 1.0 if YES won, 0.0 if NO won.
@@ -220,6 +229,10 @@ class PaperExecutor:
             reason=f"market_resolved resolution={resolution:.1f}",
             resolution=resolution,
         )
+        approx_pnl = position_cost * resolution - position_cost
         log.info("Closed position in %s, resolution=%.1f", market_id, resolution)
+        asyncio.create_task(
+            telegram.trade_closed(question or market_id, approx_pnl)
+        )
         # Approximate PnL: settlement value minus cost. Exact value is in close_pnl.
-        return position_cost * resolution - position_cost
+        return approx_pnl