dev(8948): Added functionality for multiple notes.

[michelrtm]

Fixes #8948 .

Description of the problem being solved:

The original ticket was requesting the ability to have multiple notes both for POE 1 and 2. I have had a look at the codebase and had a stab at implementing this feature request.

Instead of 1 global notes section, this PR introduces the ability to have multiple notes for a build and allows you to create, delete, reorder and set which note is active for the build, keeping the formatting of the editor.

Steps taken to verify a working solution:

1. Created a new build and opened the Notes section
2. Edited the Default note, saved, exited and reopened the build to verify that the changes were saved
3. Added a new note to the build, , saved, exited and reopened the build to verify that the changes were saved
4. Changed the active note, , saved, exited and reopened the build to verify that the changes were saved
5. Reordered the notes list, saved, exited and reopened the build to verify that the changes were saved
6. Deleted, reordered and changed notes, exited the build and discarded changes to verify no changes were saved
7. Opened a pre-existing build with notes to ensure the notes section wasn't lost
8. Saved changes to an imported build to make sure the notes were converted to the "new" format

Link to a build that showcases this PR:

1. Validate the changes introduced by this PR in an empty build
2. Used a content creator build (Crouching_Tuna) for importing a "legacy notes" build obtained from this Youtube Video
   https://maxroll.gg/poe/pob/a13ev0o0

Before screenshot:

After screenshot:

This is the new XML structure when the build is saved:

(...)
	<Notes>
		<Note id="3" title="This is renamed note reordered">
			(...)
		</Note>
		<Note id="1" active="1">
            (... Crouching_Tuna build redacted for brevity ...)
		</Note>
		<Note id="2" title="This is a new note">
			(...)
		</Note>
	</Notes>
(...)

[michelrtm]

As far as I could tell this could be a drop-in implementation in POB for POE2 as well.

[Nightblade]

Seems like a lot of note space is wasted by the new list box. Might be better if it was next to the colour buttons, and a lot shorter?