Messaging: Looply home UI and Gradle app module layout

Restructure the tree for Android Studio/Gradle builds and add the iOS-style home experience with pinned conversations, selection chrome, and scroll-aware search padding.

Co-authored-by: Cursor <cursoragent@cursor.com>

.gitignore

@@ -0,0 +1,22 @@
+*.iml
+.cursor/
+.gradle/
+/local.properties
+/.idea/
+.DS_Store
+/build/
+/captures/
+.externalNativeBuild/
+.cxx/
+app/build/
+modules/*/build/
+modules/*/.git/
+*.apk
+*.ap_
+*.dex
+*.class
+bin/
+gen/
+out/
+tools/messaging_*.png
+tools/stitch-*.txt