Protect Android native bindings from stripping (#918)

Author: sbSteveK

android/crt/build.gradle

@@ -122,7 +122,6 @@ android {
         }
         release {
             minifyEnabled false
-            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
             versionNameSuffix ""
             buildConfigField("String", "VERSION_NAME", "\"" + gitVersionName() + "\"")
         }

android/crt/consumer-rules.pro

@@ -0,0 +1,20 @@
+# Prevent shrinking and minification of aws-crt-android library
+-keep class software.amazon.awssdk.crt.** { *; }
+-keepclassmembers class software.amazon.awssdk.crt.** { *; }
+
+# Keep CrtResource subclasses (native resource management)
+-keep class * extends software.amazon.awssdk.crt.CrtResource
+
+# Keep all interfaces (callback interfaces used by native code)
+-keep interface software.amazon.awssdk.crt.** { *; }
+
+# Keep enum methods (used by JNI)
+-keepclassmembers enum software.amazon.awssdk.crt.** {
+    public static **[] values();
+    public static ** valueOf(java.lang.String);
+}
+
+# Keep JNI methods
+-keepclasseswithmembernames class * {
+    native <methods>;
+}