Rename Rust crate/API to Astryx; add walk/compress modules and clean repo artifacts

[MeridianAlgo-Developer]

Motivation

• Standardize the Rust crate and public API to the project name Astryx and provide a clear, documented implementation surface.
• Provide a self-contained, testable pure-Rust implementation of the quantum-walk-inspired hash and keep backward compatibility with the previous gaqwh names.
• Remove accidental repository artifacts and ignore build output to keep the tree clean.

Description

• Renamed crate identity to astryx in Cargo.toml/Cargo.lock and added crate-level security doc comments noting the design is experimental and unaudited.
• Added core implementation files: src/walk.rs (quantum-walk engine, state evolution, normalization, quantization) and src/compress.rs (256→64 byte compression/mixing), and composed the public API in src/lib.rs exposing astryx, astryx_256, astryx_512 while retaining gaqwh, gaqwh_256, and gaqwh_512 aliases for compatibility.
• Added unit tests in src/tests.rs covering output sizes, known vectors (256/512), avalanche, frequency balance, empty/single/long inputs, and alias compatibility.
• Cleaned repository artifacts by removing committed Python bytecode under astryx/__pycache__/ and adding target/ to .gitignore.

Testing

• Ran cargo fmt successfully.
• Ran cargo test and unit tests passed: 7 passed, 0 failed (including the crate tests in src/tests.rs).
• Ran Python tests with python -m unittest discover -s tests -q and they passed: 13 tests OK.

---

Codex Task

[chatgpt-codex-connector]

You have reached your Codex usage limits for code reviews. You can see your limits in the Codex usage dashboard.