Modernize player screen lock experience: migrate to Media3, refactor UI & lifecycle

[halilozel1903]

Motivation

• Modernize the playback stack by replacing legacy ExoPlayer artifacts with AndroidX Media3 and update the project SDK to current platform expectations.
• Improve robustness and UX by refactoring player lifecycle, state persistence, and back-navigation handling.
• Refresh the on-screen controller to a cleaner, accessible and themeable design with reusable styles and drawables.

Description

• Replaced legacy ExoPlayer dependency with Media3 modules in app/build.gradle (androidx.media3:media3-exoplayer:1.8.1, media3-exoplayer-hls, media3-ui) and raised compileSdk / targetSdk to 35.
• Rewrote MainActivity.kt to use androidx.media3.exoplayer.ExoPlayer, added robust lifecycle handling (initializePlayer, releasePlayer, savePlaybackState), saved-instance-state keys, and modern back navigation via onBackPressedDispatcher.
• Reworked layout and controller: replaced RelativeLayout player view with androidx.media3.ui.PlayerView inside a ConstraintLayout, redesigned custom_controller.xml with new drawables (bg_player_overlay, bg_control_pill, bg_bottom_panel, bg_primary_control), reusable styles (PlayerControlButton, PlayerPrimaryControlButton) and localized strings for accessibility.
• Cleaned manifest and themes, added a player-focused color palette and timebar styling, and fixed an issue in gradle.properties newline/comment formatting.

Testing

• Attempted an automated build with ./gradlew :app:assembleDebug using JAVA_HOME=/root/.local/share/mise/installs/java/17.0.2; the build could not complete because the environment blocked resolving the Android Gradle Plugin and Media3 artifacts (network tunnel returned 403 Forbidden).
• Tried switching JVM and offline modes to reproduce; Gradle still failed to resolve the plugin marker in this environment so no successful APK was produced.
• No unit or instrumentation tests were executed as part of this run due to the dependency resolution blockage.

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Codex Task

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