Change the shortcut dialog to align with the LibreOffice one

The dialog is split in 2 parts:
One shows the full list of possible shortcuts
The other shows the full list of possible actions, with a search bar and grouped by categories to facilitate browse and also with a special category 'all' (and ALL existing actions are listed, there is no "not shortcut ready" one as in MuseScore)
Selecting a shortcut shows its current binding (if any).
Selecting an action shows its shortcut (if any).
When both are selected, you can link them.
Links are additive: you can have several shortcuts for the same action (possibly keeping the "default" one and adding your own e.g., or any other reason for which you'd like to have more than one shortcut for the same action).
You can also save the set of links or load a saved set.
And you can associate shortcuts with the current app only (like Calc) or the full LibreOffice, but that last point doesn't apply to MuseScore.
Here a screen capture of the dialog after I happily linked Ctrl+W to [Insert Rows Below]

Let's also add that your personalized shortcuts are automatically displayed in the menus of LibreOffice.
For example, the ctrl+w I added for [insert row below]: