feat: 0.9.0 Android NDK native C++ compilation and Gradle integration

[sebasbad]

🤖 0.9.0 Android NDK Native C++ Compilation & Gradle Integration

📌 Executive Summary

This PR builds on top of the 0.9.0 isolate architecture (#2) to provide Android NDK C++ native shared object libraries (libllama.so for arm64-v8a), automatic Flutter Android plugin linking, and NDK cross-compilation toolchain integration.

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🔑 Key Changes & Implementation Details

1. Android NDK C++ Shared Objects (arm64-v8a):

   • Compiled libllama.so, libggml-base.so, libggml-cpu.so, libmtmd.so (Vision/VLM), and libggml.so using Android NDK toolchain (API level 26 / Oreo floor).
   • Debug info stripped via llvm-strip to keep binary sizes lightweight (libllama.so ~3.1MB).

2. Flutter Android Plugin Integration (android/):

   • Added android/build.gradle and android/src/main/AndroidManifest.xml.
   • Added android/src/main/jniLibs/arm64-v8a/ containing stripped native .so binaries for automatic Flutter Gradle embedding.

3. Platform Manifest Update (pubspec.yaml):

   • Re-added android: ffiPlugin: true under flutter.plugin.platforms.

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✅ Verification

• dart analyze: 0 Errors, 0 Warnings, 0 Hints (No issues found!).
• Binary Stripping: Verified stripped .so binaries in android/src/main/jniLibs/arm64-v8a/.

[sebasbad]

Closing in favor of main and upstream draft PR netdur#111.

Context:
The repository main branch has been synced with upstream/main (v0.9.0-dev.12), which natively handles Android NDK asset building. Upstream draft PR netdur#111 (feat/cocoapods-swiftpm-dual-support) consolidates mobile platform compatibility.