[LLM] build: migrate to AboutLibraries and upgrade build toolchain

[menny]

Summary

Fixes #166 and resolves build/dependency incompatibilities from #154.

Problem

1. F-Droid Build Failure (F-Droid can't build #166): com.google.android.gms:play-services-oss-licenses uses a proprietary Google SDK license, causing F-Droid's build scanners to reject the application.
2. Build Toolchain Incompatibilities (Update App dependencies #154): Updating Hilt to 2.60.1 required AGP 9.0+, which in turn required Gradle 9.6+, built-in Kotlin plugin migration, and managed device DSL adjustments.

Solution

• FLOSS License Collection: Replaced Google OSS Licenses plugin and runtime with AboutLibraries (com.mikepenz.aboutlibraries.plugin.android:15.2.0 and aboutlibraries-compose-m3:15.2.0), which is 100% Apache-2.0 FLOSS across all flavors.
• UI Simplification: Replaced manual raw-resource parsing in AboutScreen.kt with AboutLibraries' native Compose Material 3 LibrariesContainer.
• Toolchain Upgrades:
  • Android Gradle Plugin upgraded from 8.13.2 to 9.4.0
  • Gradle wrapper upgraded from 9.3.1 to 9.7.1
  • KSP upgraded to 2.3.11, Compose BOM to 2026.08.00, Dropshots to 0.6.0
  • Migrated managedDevices DSL to localDevices and removed obsolete standalone Kotlin plugin applications
• Tests & Verification: Added AboutScreenTest and stabilized Turbine test timeouts in HistoryViewModelTest.

Closes #166

[anysoftkeyboard-bot]

This PR is a solid and clean migration from Google's play-services-oss-licenses to AboutLibraries. Replacing the proprietary Google plugin with a 100% FLOSS solution resolves F-Droid build scanner issues (#166). The UI simplifies nicely using LibrariesContainer, keep.xml guarantees resource preservation under R8 shrinking, and the test improvements in HistoryViewModelTest and AboutScreenTest enhance build stability and coverage. Great work!

[anysoftkeyboard-bot]

Replacing play-services-oss-licenses with AboutLibraries resolves F-Droid build Scanner issues, simplifies license parsing in AboutScreen, and stabilizes unit test execution timing in HistoryViewModelTest.

[anysoftkeyboard-bot]

Solid and clean migration from Google's play-services-oss-licenses to AboutLibraries, resolving F-Droid build scanner issues, simplifying UI, and improving test stability.