closes #2416 
This PR addresses the following improvements and fixes in the chat
message UI for assistant messages:

Commit Hash Display: The commit hash is now shown as a sibling to the
commit message in the metadata row, following the commit message and
icon.
Minimal Tooltip: The tooltip for the commit hash now displays only the
commit hash itself (no commit message or extra text), providing a clean
and focused UX.
Copy-to-Clipboard: Users can copy the full commit hash by clicking the
hash or copy icon
<img width="769" height="199" alt="image"
src="https://github.com/user-attachments/assets/9b28db64-6521-4ee7-b46c-a3b9e8ee9389"
/>


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