Improve spinner in bash mode to make it more clear the bash command is running

Bug Description
when I type "!" and then a bash command it seems like claude is still trying to figure out what to do instead of just running the bash command

Environment Info

• Platform: macos
• Terminal: WarpTerminal
• Version: 0.2.41
• Feedback ID: f302cbda-69fd-486c-94e8-b43445b155df

<img width="839" alt="Image" src="https://github.com/user-attachments/assets/e3735c73-c734-4199-9f26-800b22adac33" />