The commit button on the top right of the header bar doesn't have any tooltip...

The commit button on the top right of the header bar doesn't have any tooltip, and it can be accidentally clicked. Therefore, it would be better if clicking on Commit pops up a confirmation modal (with an addition of showing file diffs) and tell developers what it does.

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| Field | Value |
| --- | --- |
| App version | 1.0.25 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 2 |

Start by running the app and opening the /chat path, then inspect the top-right header and the Commit control. Trace where that control is rendered and how its pending file changes are exposed. Done means the control explains its action, requires confirmation, and shows the relevant file diffs before committing.

Written by the indexing model from the issue text.