Desktop: Fixes #10815: Fix Enter key submits dialogs even if a button has focus

[personalizedrefrigerator]

Summary

This pull request fixes several issues with the same underlying cause:

• Pressing Enter after focusing the "OK" button in the "Create Notebook" dialog created 3 notebooks rather than just 1.
• Pressing Enter when trying to edit a field in the Note Properties dialog closed the dialog and saved changes instead.
• Similar issues where Enter is intended by the user to activate a button or link, but instead dismisses the dialog.

This commit causes Enter to only submit a dialog if the "OK" button or an input has focus. This does not affect how the Escape key is handled.

Fixes #10815.

Notes

• In many dialogs ("add tag", "add profile", "add notebook", and "note properties" dialogs) either a text input or the "OK" button has the default focus. As such, in these cases, pressing Enter with the default item focused still submits the dialog.
• This should not affect plugin dialogs.
  • Brief testing was done with the note diff plugin by opening its note chooser dialog, selecting a note such that the "OK" button is visible, and pressing Enter.

Testing plan

Manual testing (MacOS):

1. Open the "share" dialog for a notebook.
2. Enter a recipient's email and press tab to focus the "share" button.
3. Press enter.
4. Verify that the recipient is added to the recipient list without the dialog closing.
5. Press escape.
6. Verify that the dialog is now closed.
7. Open the "New Notebook" dialog.
8. Type a title.
9. Press Enter.
10. Verify that the new notebook has been created.
11. Repeat steps 7-8.
12. Navigate to the "OK" button with the Tab key.
13. Press Enter.
14. Verify that just one notebook is created.
15. Create a new note.
16. Open the "note properties" dialog.
17. Use the tab key to navigate to the "Edit" button for "Location".
18. Press Enter.
19. Verify that an input is shown and that the dialog is still visible.
20. Make a small change and press Enter.
21. Verify that the dialog has closed.
22. Re-open the dialog and verify that the change was saved.