fix(telegram): dedupe webhook+polling updates via shared DB guard

Webhook (Flask) and polling (momo-telegram-bot) consumed the same
Telegram update_id, causing /menu callbacks to fire twice. Add a
shared dedup module backed by telegram_update_dedup table (300s TTL,
60s cleanup) with in-memory fallback, wired into both paths.

Polling launcher now skips startup when webhook is configured to
prevent dual-consumption at the source.

38 tests across webhook, menu keyboards, telegram_api, dedup guard,
and trend bot service.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/tools/run_telegram_bot.py

@@ -85,6 +85,12 @@ async def main():
     # 建立 Bot 服務
     bot_service = TelegramBotService(token)
 
+    if not bot_service.should_run_polling():
+        logger.warning(
+            "Webhook 已設定，Polling Bot 已跳過啟動；請使用 OpenClaw webhook 路徑處理互動。"
+        )
+        return
+
     # 取得 Application
     app = bot_service.get_application()