Nix package / NixOS derivation

[vmvarela]

Description

Write a Nix derivation so NixOS and nix-on-any-OS users can install sql-pipe declaratively.

Acceptance Criteria

• nix/sql-pipe.nix derivation created that fetches the pre-built binary
• Works with nix-env -i and as a nix-shell dependency
• SHA256 hash verified
• README documents the Nix installation method

Notes

• Start with a binary-fetching derivation; a source build can come later
• Path to nixpkgs inclusion requires following https://github.com/NixOS/nixpkgs/blob/master/CONTRIBUTING.md