fix(gateway): accept finalize kwarg in all platform edit_message overrides

stream_consumer._send_or_edit unconditionally passes finalize= to
adapter.edit_message(), but only DingTalk's override accepted the
kwarg. Streaming on Telegram/Discord/Slack/Matrix/Mattermost/Feishu/
WhatsApp raised TypeError the first time a segment break or final
edit fired.

The REQUIRES_EDIT_FINALIZE capability flag only gates the redundant
final edit (and the identical-text short-circuit), not the kwarg
itself — so adapters that opt out of finalize still receive the
keyword argument and must accept it.

Add *, finalize: bool = False to the 7 non-DingTalk signatures; the
body ignores the arg since those platforms treat edits as stateless
(consistent with the base class contract in base.py).

Add a parametrized signature check over every concrete adapter class
so a future override cannot silently drop the kwarg — existing tests
use MagicMock which swallows any kwarg and cannot catch this.

Fixes #12579

gateway/platforms/discord.py

@@ -1081,6 +1081,8 @@ class DiscordAdapter(BasePlatformAdapter):
         chat_id: str,
         message_id: str,
         content: str,
+        *,
+        finalize: bool = False,
     ) -> SendResult:
         """Edit a previously sent Discord message."""
         if not self._client:

gateway/platforms/feishu.py

@@ -1468,6 +1468,8 @@ class FeishuAdapter(BasePlatformAdapter):
         chat_id: str,
         message_id: str,
         content: str,
+        *,
+        finalize: bool = False,
     ) -> SendResult:
         """Edit a previously sent Feishu text/post message."""
         if not self._client:

gateway/platforms/matrix.py

@@ -825,7 +825,7 @@ class MatrixAdapter(BasePlatformAdapter):
 
 
     async def edit_message(
-        self, chat_id: str, message_id: str, content: str
+        self, chat_id: str, message_id: str, content: str, *, finalize: bool = False
     ) -> SendResult:
         """Edit an existing message (via m.replace)."""
 

gateway/platforms/mattermost.py

@@ -304,7 +304,7 @@ class MattermostAdapter(BasePlatformAdapter):
         )
 
     async def edit_message(
-        self, chat_id: str, message_id: str, content: str
+        self, chat_id: str, message_id: str, content: str, *, finalize: bool = False
     ) -> SendResult:
         """Edit an existing post."""
         formatted = self.format_message(content)

gateway/platforms/slack.py

@@ -316,6 +316,8 @@ class SlackAdapter(BasePlatformAdapter):
         chat_id: str,
         message_id: str,
         content: str,
+        *,
+        finalize: bool = False,
     ) -> SendResult:
         """Edit a previously sent Slack message."""
         if not self._app:

gateway/platforms/telegram.py

@@ -1081,6 +1081,8 @@ class TelegramAdapter(BasePlatformAdapter):
         chat_id: str,
         message_id: str,
         content: str,
+        *,
+        finalize: bool = False,
     ) -> SendResult:
         """Edit a previously sent Telegram message."""
         if not self._bot:

gateway/platforms/whatsapp.py

@@ -655,6 +655,8 @@ class WhatsAppAdapter(BasePlatformAdapter):
         chat_id: str,
         message_id: str,
         content: str,
+        *,
+        finalize: bool = False,
     ) -> SendResult:
         """Edit a previously sent message via the WhatsApp bridge."""
         if not self._running or not self._http_session: