perf: strip redundant blanket proguard keeps for DEX shrink/obfuscation

android/app/proguard-rules.pro

@@ -1,23 +1,9 @@
-# Flutter specific
--keep class io.flutter.app.** { *; }
--keep class io.flutter.plugin.**  { *; }
--keep class io.flutter.util.**  { *; }
--keep class io.flutter.view.**  { *; }
--keep class io.flutter.**  { *; }
--keep class io.flutter.plugins.**  { *; }
-
 # Play Core deferred components
 -dontwarn com.google.android.play.core.**
 -dontwarn com.google.android.play.core.splitcompat.**
 -dontwarn com.google.android.play.core.splitinstall.**
 -dontwarn com.google.android.play.core.tasks.**
 
-# SIAB Scale app
--keep class id.ptsemangat.siab_scale.** { *; }
-
-# flutter_blue_plus
--keep class com.lib.flutter_blue_plus.** { *; }
-
-# sqflite
--keep class com.tekartik.sqflite.** { *; }
-
+# Aggressive R8 optimization (missing from default configs)
+-allowaccessmodification
+-repackageclasses ''