Add R8 keep rule for Hilt_* base classes to fix ClassCastException in release builds

Use -keep,allowobfuscation,allowshrinking instead of bare -keep so that
R8 can still rename and remove unused Hilt_* classes while preventing
vertical class merging that breaks the bytecode-transformed hierarchy.

Fixes #4668

Author: Senthil455

hilt-android/main/resources/META-INF/com.android.tools/proguard/hilt-android.pro

@@ -2,4 +2,9 @@
 # See b/183070411#comment4 for more info.
 -keep,allowobfuscation,allowshrinking @dagger.hilt.internal.ComponentEntryPoint class *
 -keep,allowobfuscation,allowshrinking @dagger.hilt.internal.GeneratedEntryPoint class *
--keep,allowobfuscation,allowshrinking @dagger.hilt.android.EarlyEntryPoint class *
+-keep,allowobfuscation,allowshrinking @dagger.hilt.android.EarlyEntryPoint class *
+
+# Prevent R8 full mode from vertically merging Hilt_* base classes with
+# @AndroidEntryPoint user classes. The bytecode transform rewrites user classes
+# to extend Hilt_*; vertical class merging breaks this hierarchy.
+-keep,allowobfuscation,allowshrinking class **.Hilt_*

hilt-android/main/resources/META-INF/com.android.tools/r8/hilt-android.pro

@@ -2,4 +2,9 @@
 # See b/183070411#comment4 for more info.
 -keep,allowobfuscation,allowshrinking @dagger.hilt.internal.ComponentEntryPoint class *
 -keep,allowobfuscation,allowshrinking @dagger.hilt.internal.GeneratedEntryPoint class *
--keep,allowobfuscation,allowshrinking @dagger.hilt.android.EarlyEntryPoint class *
+-keep,allowobfuscation,allowshrinking @dagger.hilt.android.EarlyEntryPoint class *
+
+# Prevent R8 full mode from vertically merging Hilt_* base classes with
+# @AndroidEntryPoint user classes. The bytecode transform rewrites user classes
+# to extend Hilt_*; vertical class merging breaks this hierarchy.
+-keep,allowobfuscation,allowshrinking class **.Hilt_*