v3.2.0

• feat: Install purple on NixOS, or with Nix on Linux and macOS.
• feat: nix profile install github:erickochen/purple adds purple to your Nix profile in one command. Same single binary as every other channel.
• feat: nix develop github:erickochen/purple drops you into a pinned Rust toolchain with cargo-audit and cargo-deny ready, so contributors get the exact same environment as CI.
• feat: Hash-locked flake inputs for reproducible builds. NixOS users can embed purple as a flake input with the follows-pattern recipe in the wiki.
• Initial flake foundation contributed by @ArisoN-ext (#54).