Fix: remove custom fonts, add launcher icons

- Remove JetBrainsMono font assets (using google_fonts instead)
- Add adaptive icon and PNG fallbacks for launcher
- Build successful: app-release.apk (23.7MB)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

android/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-all.zip