Make actions editable

- Pull appearance information into a separate object.
- Return action ID to action provider.
- Allow action appearance to be updated by ID.
- Allow actions to be removed by ID.

Bug: 329659738
Test: atest ScreenshotViewModelTest
Flag: ACONFIG com.android.systemui.screenshot_shelf_ui DEVELOPMENT
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:79de0412b6dca6dd2401684575ba507683aa0775)
Merged-In: I5a5729cc1e4bb021efb441e367fdac0ee72bc723
Change-Id: I5a5729cc1e4bb021efb441e367fdac0ee72bc723