feat: add optional custom argument topic override via Web UI

- Added optional 'topic' field to BipolarTriggerRequest model
- Added topic parameter to force_trigger_argument and force_trigger_argument_from_message_id
- Updated run_argument to accept optional custom topic (None=random, ''=no topic, str=custom)
- Added topic input field to Web UI trigger-argument section
- Updated JS to send topic in API request body
- Custom topics bypass the random rotation system, allowing manual theme control

bot/routes/bipolar_mode.py

@@ -129,7 +129,7 @@ def trigger_argument(data: BipolarTriggerRequest):
     if message_id:
         async def trigger_from_message():
             success, error = await force_trigger_argument_from_message_id(
-                channel_id, message_id, globals.client, data.context
+                channel_id, message_id, globals.client, data.context, topic=data.topic
             )
             if not success:
                 logger.error(f"Failed to trigger argument from message: {error}")
@@ -148,8 +148,8 @@ def trigger_argument(data: BipolarTriggerRequest):
     if not channel:
         return JSONResponse(status_code=404, content={"status": "error", "message": f"Channel {channel_id} not found"})
 
-    # Trigger the argument
-    globals.client.loop.create_task(force_trigger_argument(channel, globals.client, data.context))
+    # Trigger the argument with optional custom topic
+    globals.client.loop.create_task(force_trigger_argument(channel, globals.client, data.context, topic=data.topic))
 
     return {
         "status": "ok",