feat(gateway): make the working-state status text configurable

Adds PlatformConfig.typing_status_text for the two platforms that render
text for the working-state line: Slack's assistant.threads.setStatus
status (hardcoded 'is thinking...') and Google Chat's visible marker
message (hardcoded 'Hermes is thinking…'). None keeps each platform's
built-in default; to_dict omits the field when unset so existing configs
serialize unchanged. Plumbing mirrors typing_indicator exactly (typed
field, from_dict extra fallback, shared-key bridge).

Also documents that Slack's status line requires the assistant:write
scope — without it setStatus fails silently and Slack shows its own
generic placeholder, which previously made the behaviour undiagnosable
from config alone.

plugins/platforms/google_chat/adapter.py

@@ -2678,7 +2678,10 @@ class GoogleChatAdapter(BasePlatformAdapter):
         thread_id = self._resolve_thread_id(
             reply_to=None, metadata=metadata, chat_id=chat_id,
         )
-        body: Dict[str, Any] = {"text": "Hermes is thinking…"}
+        body: Dict[str, Any] = {
+            "text": getattr(self.config, "typing_status_text", None)
+            or "Hermes is thinking…"
+        }
         if thread_id:
             body["thread"] = {"name": thread_id}
 

plugins/platforms/slack/adapter.py

@@ -1574,7 +1574,8 @@ class SlackAdapter(BasePlatformAdapter):
     async def send_typing(self, chat_id: str, metadata=None) -> None:
         """Show a typing/status indicator using assistant.threads.setStatus.
 
-        Displays "is thinking..." next to the bot name in a thread.
+        Displays "is thinking..." next to the bot name in a thread, or the
+        platform's ``typing_status_text`` config value when set.
         Requires the assistant:write or chat:write scope.
         Auto-clears when the bot sends a reply to the thread.
         """
@@ -1602,7 +1603,8 @@ class SlackAdapter(BasePlatformAdapter):
             await self._get_client(chat_id, team_id=team_id).assistant_threads_setStatus(
                 channel_id=chat_id,
                 thread_ts=thread_ts,
-                status="is thinking...",
+                status=getattr(self.config, "typing_status_text", None)
+                or "is thinking...",
             )
         except Exception as e:
             # Silently ignore — may lack assistant:write scope or not be