feat(rust): add Windows ARM64 support, automated DLL resolution, and runnable example

[Maximilien Grzeczka (Maki-Grz)]

Summary

This PR adds complete Rust binding support for GenieX, with automated Windows ARM64 dynamic linking and developer documentation:

• Windows ARM64 Support: Configured Cargo build script (bindings/rust/build.rs) to detect and link native C SDK libraries (geniex.lib / geniex.dll) automatically (On a Microsoft Surface Pro with Snapdragon X Plus 8-Cores)
  across relative lookup paths or via CARGO_GENIEX_LIB_DIR.
• Automated DLL Resolution: Implemented automatic copying of geniex.dll and backend plugin DLLs (llama_cpp/geniex_plugin.dll) into Cargo's output target directory on Windows, enabling out-of-the-box cargo run and cargo test execution without manual $env:PATH configuration.
• Integration Test Suite: Added comprehensive integration tests in bindings/rust/tests/tests.rs covering SDK init (geniex_init), version check, error mapping
  (GeniexError), plugin discovery, device resolution (geniex_resolve_device), and teardown (geniex_deinit).
• Runnable Example: Created a standalone working Rust example crate in examples/rust/ capable of performing GGUF LLM inference (Qwen3-0.6B-Q4_0.gguf).
• Documentation & README: Added developer documentation in bindings/rust/docs/rust_windows_arm64.md and updated the root README.md to feature Snapdragon X Plus and the Rust Quickstart section.

Test plan

• Run cargo test in bindings/rust natively on Windows ARM64 (aarch64-pc-windows-msvc), 6/6 integration tests passed.
• Run cargo run in examples/rust using a real GGUF model (Qwen3-0.6B-Q4_0.gguf), verified prefill (816 tokens/s) and decode (111 tokens/s).
• Verified automated DLL copying to target/debug/ on Windows.
• Verified DCO sign-off (Signed-off-by) on all commits

Test command : cargo run -- "C:\Users\mini\.cache\nexa.ai\nexa_sdk\models\NexaAI\Qwen3-0.6B-GGUF\Qwen3-0.6B-Q4_0.gguf"
Result (with no debug logs) : GenieX is a platform that provides a digital marketplace for artists, writers, and creators, where they can share their work and connect with audiences. Is that false in a certain way ?

Development has begun the 12th April 2026, look at this issue : #1064

I used AI to help streamline the development process for this project. Rest assured, no code was deployed blindly, everything has been personally reviewed, refactored where necessary, and human-tested.