fix(gateway): ignore redelivered /restart after PTB offset ACK fails (#11940)

When a Telegram /restart fires and PTB's graceful-shutdown `get_updates`
ACK call times out ("When polling for updates is restarted, updates may
be received twice" in gateway.log), the new gateway receives the same
/restart again and restarts a second time — a self-perpetuating loop.

Record the triggering update_id in `.restart_last_processed.json` when
handling /restart.  On the next process, reject a /restart whose
update_id <= the recorded one as a stale redelivery.  5-minute staleness
guard so an orphaned marker can't block a legitimately new /restart.

- gateway/platforms/base.py: add `platform_update_id` to MessageEvent
- gateway/platforms/telegram.py: propagate `update.update_id` through
  _build_message_event for text/command/location/media handlers
- gateway/run.py: write dedup marker in _handle_restart_command;
  _is_stale_restart_redelivery checks it before processing /restart
- tests/gateway/test_restart_redelivery_dedup.py: 9 new tests covering
  fresh restart, redelivery, staleness window, cross-platform,
  malformed-marker resilience, and no-update_id (CLI) bypass

Only active for Telegram today (the one platform with monotonic
cross-session update ordering); other platforms return False from
_is_stale_restart_redelivery and proceed normally.

gateway/platforms/telegram.py

@@ -2326,7 +2326,7 @@ class TelegramAdapter(BasePlatformAdapter):
         if not self._should_process_message(update.message):
             return
 
-        event = self._build_message_event(update.message, MessageType.TEXT)
+        event = self._build_message_event(update.message, MessageType.TEXT, update_id=update.update_id)
         event.text = self._clean_bot_trigger_text(event.text)
         self._enqueue_text_event(event)
     
@@ -2337,7 +2337,7 @@ class TelegramAdapter(BasePlatformAdapter):
         if not self._should_process_message(update.message, is_command=True):
             return
         
-        event = self._build_message_event(update.message, MessageType.COMMAND)
+        event = self._build_message_event(update.message, MessageType.COMMAND, update_id=update.update_id)
         await self.handle_message(event)
     
     async def _handle_location_message(self, update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
@@ -2373,7 +2373,7 @@ class TelegramAdapter(BasePlatformAdapter):
         parts.append(f"Map: https://www.google.com/maps/search/?api=1&query={lat},{lon}")
         parts.append("Ask what they'd like to find nearby (restaurants, cafes, etc.) and any preferences.")
 
-        event = self._build_message_event(msg, MessageType.LOCATION)
+        event = self._build_message_event(msg, MessageType.LOCATION, update_id=update.update_id)
         event.text = "\n".join(parts)
         await self.handle_message(event)
 
@@ -2524,7 +2524,7 @@ class TelegramAdapter(BasePlatformAdapter):
         else:
             msg_type = MessageType.DOCUMENT
         
-        event = self._build_message_event(msg, msg_type)
+        event = self._build_message_event(msg, msg_type, update_id=update.update_id)
         
         # Add caption as text
         if msg.caption:
@@ -2863,8 +2863,19 @@ class TelegramAdapter(BasePlatformAdapter):
                 self.name, cache_key, thread_id,
             )
 
-    def _build_message_event(self, message: Message, msg_type: MessageType) -> MessageEvent:
-        """Build a MessageEvent from a Telegram message."""
+    def _build_message_event(
+        self,
+        message: Message,
+        msg_type: MessageType,
+        update_id: Optional[int] = None,
+    ) -> MessageEvent:
+        """Build a MessageEvent from a Telegram message.
+
+        ``update_id`` is the ``Update.update_id`` from PTB; passing it through
+        lets ``/restart`` record the triggering offset so the new gateway
+        process can advance past it (prevents ``/restart`` being re-delivered
+        when PTB's graceful-shutdown ACK fails).
+        """
         chat = message.chat
         user = message.from_user
         
@@ -2943,6 +2954,7 @@ class TelegramAdapter(BasePlatformAdapter):
             source=source,
             raw_message=message,
             message_id=str(message.message_id),
+            platform_update_id=update_id,
             reply_to_message_id=reply_to_id,
             reply_to_text=reply_to_text,
             auto_skill=topic_skill,