- Replace library dropdown in MoveToLibraryModal with flex-wrap shortcut buttons
- Each button has one letter underlined as a keyboard shortcut (greedy first-unused-letter assignment)
- Pressing the shortcut key selects the library and immediately triggers the move
- If the target library has multiple folders, folder picker appears before moving
- Add Alt+M as an alias for the existing Ctrl+Shift+M Move to Library shortcut
- Update docs and artifacts index
