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/notify/telegram.py

@@ -0,0 +1,53 @@
+"""Telegram notifications — fire-and-forget, never blocks trade execution."""
+import logging
+import os
+
+import httpx
+
+log = logging.getLogger(__name__)
+
+_TOKEN   = os.getenv("TELEGRAM_BOT_TOKEN", "")
+_CHAT_ID = os.getenv("TELEGRAM_CHAT_ID", "")
+
+
+async def _send(text: str) -> None:
+    """POST a message to Telegram. Swallows all errors silently."""
+    if not _TOKEN or not _CHAT_ID:
+        return
+    try:
+        async with httpx.AsyncClient(timeout=10) as client:
+            resp = await client.post(
+                f"https://api.telegram.org/bot{_TOKEN}/sendMessage",
+                json={"chat_id": _CHAT_ID, "text": text},
+            )
+            if resp.status_code != 200:
+                log.warning("Telegram %d: %s", resp.status_code, resp.text[:200])
+    except Exception as exc:
+        log.warning("Telegram notification failed: %s", exc)
+
+
+async def trade_opened(question: str, direction: str, size_usdc: float, edge_net: float) -> None:
+    emoji = "📈" if direction == "BUY_YES" else "📉"
+    await _send(
+        f"{emoji} TRADE ABIERTO\n"
+        f"{question[:80]}\n"
+        f"Dir: {direction}  Size: ${size_usdc:.2f}  Edge: {edge_net:+.3f}"
+    )
+
+
+async def trade_closed(question: str, pnl: float) -> None:
+    emoji = "✅" if pnl > 0 else "❌"
+    result = "GANADO" if pnl > 0 else "PERDIDO"
+    await _send(
+        f"{emoji} {result}\n"
+        f"{question[:80]}\n"
+        f"PnL: {pnl:+.2f} USDC"
+    )
+
+
+async def trade_legacy_closed(question: str, recovered: float, reason: str) -> None:
+    await _send(
+        f"🔒 LEGACY CLOSE\n"
+        f"{question[:80]}\n"
+        f"Recuperado: ${recovered:.2f}  |  {reason[:60]}"
+    )