### Context
Adds a keyboard shortcut for saving a notebook in the explorer
<img width="269" height="112" alt="image"
src="https://github.com/user-attachments/assets/c9ab1c4b-fbb3-40ed-8f10-47301e16e6b3"
/>
Also shifts the keyboard shortcuts for queue operations into the table
editor registry - more contextual to there since queue operations is
specifically for the table editor only
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
- **New Features**
- Added a keyboard shortcut (`Mod+S`) for saving notebooks in Explorer.
- The save toolbar action now displays its keyboard shortcut.
- Restored table editing shortcuts for saving pending edits, toggling
the operation queue, and undoing changes (`Mod+S`, `Mod+.`, and
`Mod+Z`).
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Joshen Lim
aef1599d3e