fix: Per chat Wild mode Follow up

[GindaChen]

Follow up:

• Pause and stop is still not super great yet. The stop button at the botton conflict with the pause / resume button on the top. The behavior should be: the pause and resume button is put near the send button. Then, we have choice to (a) stop the entire wild loop - which is consistent with the existing stop button, (b) pause the wild loop. So we only need to maintain 2 more buttons.
• Clicking pause or stop makes the wild mode badge disappear. Make sure the wild mode badge is on and reflect the status of the wild mode: if it is paused, have a pause icon at the front; if it is stopped, same. Show the wild mode until user switch to different modes.
• When wild mode is on, user cannot switch this conversation from wild mode to other mode.

Originally posted by @GindaChen in #264 (comment)