Navigation and other improvements

[harshad1]

This adds several improvements to file browsing and navigation

1. Better handling + fixes to handling of special / virtual folders
2. back goes to previous folder (needs to be refined more). Addresses #2337
3. Fixed activity back-stack and link navigation

Todo:

• [x] Fix file dialog subtitle padding and truncation
• [x] Back should ask before closing markor

I have also added other things to this PR now

1. Highlighting happens in a separate thread making it less janky when typing fast (especially in very long todo lists)
2. We had a lot of code which did not check if selection was invalid - added defensive logic everywhere
3. Several cleanups
4. Remember share into format as link state from last time

[harshad1]

This is ready imo

[harshad1]

@gsantner Do you know why this build is failing?

[gsantner]

Seems that either a repository went down under, or GitHub actions has network issues (which also happens from time to time). It would be weird if suddenly two libraries would go to nirvana on it's own.

Could not resolve all files for configuration ':app:flavorDefaultDebugRuntimeClasspath'. Failed to transform library-1.1.8.aar (com.pixplicity.generate:library:1.1.8) to match attributes {artifactType=android-aar-metadata, org.gradle.category=library, org.gradle.libraryelements=jar, org.gradle.status=release, org.gradle.usage=java-runtime}. > Could not find library-1.1.8.jar (com.pixplicity.generate:library:1.1.8). Searched in the following locations: https://jcenter.bintray.com/com/pixplicity/generate/library/1.1.8/library-1.1.8.aar https://jcenter.bintray.com/com/pixplicity/generate/library/1.1.8/library-1.1.8.jar Failed to transform om-recorder-1.1.5.aar (com.kailashdabhi:om-recorder:1.1.5) to match attributes {artifactType=android-aar-metadata, org.gradle.category=library, org.gradle.libraryelements=jar, org.gradle.status=release, org.gradle.usage=java-runtime}. > Could not find om-recorder-1.1.5.jar (com.kailashdabhi:om-recorder:1.1.5). Searched in the following locations: https://jcenter.bintray.com/com/kailashdabhi/om-recorder/1.1.5/om-recorder-1.1.5.aar https://jcenter.bintray.com/com/kailashdabhi/om-recorder/1.1.5/om-recorder-1.1.5.jar

[harshad1]

Also now included are fixes for the build failing.

@gsantner this is ready to merge

[gsantner]

Thanks, merging