Migrated Custom Image Selector to Jetpack Compose

[rohit9625]

Description (required)

Fixes #5963

What changes did you make and why?
I've created the UI for the Custom Image Selector with some minor UI changes. We can't upload from Custom Selector as I am still working on it. Please feel free to test this branch on your device and let me know your thoughts. I am open to suggestions on the UI and functionality.

Tests performed (required)

Tested ProdDebug on Samsung A14 with API level 34.

Screenshots (for UI changes only)

[nicolas-raoul]

I know it is a draft, but I could not resist trying 😊
It looks great and feels faster!
Not sure if useful but here are some observations:

I get this when coming from a previous version of the app:

java.lang.RuntimeException: Unable to start activity ComponentInfo{fr.free.nrw.commons/fr.free.nrw.commons.customselector.ui.selector.CustomSelectorActivity}: java.lang.NullPointerException: findViewById(...) must not be null
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:4129)

After deleting the app's data it opens fine.

When I select a pic and tap "Upload" or "Mark as not for upload", nothing happens.

I see no "Show already actioned images" switch.

After long-pressing a picture, I can not swipe it up (select for upload) or down (mark as not for upload).

[rohit9625]

Thank you @nicolas-raoul for your valuable feedback 😊