Initial commit: Pezkuwi Wallet Android

Security hardened release:
- Code obfuscation enabled (minifyEnabled=true, shrinkResources=true)
- Sensitive files excluded (google-services.json, keystores)
- Branch.io key moved to BuildConfig placeholder
- Updated dependencies: OkHttp 4.12.0, Gson 2.10.1, BouncyCastle 1.77
- Comprehensive ProGuard rules for crypto wallet
- Navigation 2.7.7, Lifecycle 2.7.0, ConstraintLayout 2.1.4

bindings/metadata_shortener/src/main/AndroidManifest.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+</manifest>

bindings/metadata_shortener/src/main/java/io/novafoundation/nova/metadata_shortener/MetadataShortener.java

@@ -0,0 +1,30 @@
+package io.novafoundation.nova.metadata_shortener;
+
+public class MetadataShortener {
+
+    static {
+        System.loadLibrary("metadata_shortener_java");
+    }
+
+    public static native byte[] generate_extrinsic_proof(
+        byte[] call,
+        byte[] signed_extras,
+        byte[] additional_signed,
+        byte[] metadata,
+
+        int spec_version,
+        String spec_name,
+        int base58_prefix,
+        int decimals,
+        String token_symbol
+    );
+
+    public static native byte[] generate_metadata_digest(
+        byte[] metadata,
+        int spec_version,
+        String spec_name,
+        int base58_prefix,
+        int decimals,
+        String token_symbol
+    );
+}