fix(whatsapp): add **kwargs to media sending methods to accept metadata (#3571)

The base orchestrator passes metadata=_thread_metadata to
send_image_file, send_video, and send_document. WhatsApp was the
only platform adapter missing the parameter, causing TypeError
crashes when sending media.

Extended to all three methods (original PR only fixed send_image_file).


Salvaged from PR #3144.

Co-authored-by: afifai <afifai@users.noreply.github.com>

gateway/platforms/whatsapp.py

@@ -526,6 +526,7 @@ class WhatsAppAdapter(BasePlatformAdapter):
         image_path: str,
         caption: Optional[str] = None,
         reply_to: Optional[str] = None,
+        **kwargs,
     ) -> SendResult:
         """Send a local image file natively via bridge."""
         return await self._send_media_to_bridge(chat_id, image_path, "image", caption)
@@ -536,6 +537,7 @@ class WhatsAppAdapter(BasePlatformAdapter):
         video_path: str,
         caption: Optional[str] = None,
         reply_to: Optional[str] = None,
+        **kwargs,
     ) -> SendResult:
         """Send a video natively via bridge — plays inline in WhatsApp."""
         return await self._send_media_to_bridge(chat_id, video_path, "video", caption)
@@ -547,6 +549,7 @@ class WhatsAppAdapter(BasePlatformAdapter):
         caption: Optional[str] = None,
         file_name: Optional[str] = None,
         reply_to: Optional[str] = None,
+        **kwargs,
     ) -> SendResult:
         """Send a document/file as a downloadable attachment via bridge."""
         return await self._send_media_to_bridge(