fix(telegram): detect unsupported rich stream edits

nanobot/channels/telegram/runtime.py

@@ -938,7 +938,13 @@ class TelegramChannel(BaseChannel):
                 # edit overwrite the already-successful rich result.
                 self.logger.debug("Rich stream edit already applied for {}", chat_id)
                 return True
-            if self._is_rich_capability_error(exc):
+            # Before Bot API 10.1, editMessageText ignores rich_message and
+            # reports the absent text argument instead.
+            pre_rich_edit_server = (
+                bool(content)
+                and str(exc).strip().lower() == "message text is empty"
+            )
+            if self._is_rich_capability_error(exc) or pre_rich_edit_server:
                 self.logger.debug("editMessageText rich_message not available, disabling")
                 self._rich_send_disabled = True
                 return False

nanobot/channels/telegram/tests/test_telegram_channel.py

@@ -2777,7 +2777,10 @@ async def test_send_delta_stream_end_rich_capability_error_latches_and_falls_bac
         MessageBus(),
     )
     _install_ready_app(channel)
-    channel._app.bot.do_api_request = AsyncMock(side_effect=BadRequest("Method not found"))
+    # Before Bot API 10.1, editMessageText ignores rich_message and requires text.
+    channel._app.bot.do_api_request = AsyncMock(
+        side_effect=BadRequest("Message text is empty")
+    )
     channel._app.bot.edit_message_text = AsyncMock()
     channel._stream_bufs["123"] = _StreamBuf(text="hello", message_id=7, last_edit=0.0)