flake.lock: Update

Flake lock file updates:

• Updated input 'fenix':
    'github:nix-community/fenix/25db7a6f4de7dea678620785e03fbc4560c00672?narHash=sha256-wC9PR%2BrPjmcpnPdOIDwyNwQiRhNsuDs3oZY3t42f4uA%3D' (2025-07-26)
  → 'github:nix-community/fenix/acdb7d8af407ea8aee21b028dc58b4bc51a7849a?narHash=sha256-2cMDogXcqv975o191g0/6ZM0UolJ2X0ChuuLaNKbNAM%3D' (2025-08-02)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/51e77c9d7b9b99f7a230bf5179ef1343befd71ac?narHash=sha256-5XbVpJwiy%2Bsw1v4PXSAz4lgJnVna6xkzqyZtoHymFJA%3D' (2025-07-25)
  → 'github:rust-lang/rust-analyzer/68e7ec90bf29c9b17d0dcdb3358de5dee7f4afb5?narHash=sha256-Ya4Ecj8JaKkapgYCCybzZBcypXpblhuG0hVDzdy2zyo%3D' (2025-07-31)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/6027c30c8e9810896b92429f0092f624f7b1aace?narHash=sha256-cnL5WWn/xkZoyH/03NNUS7QgW5vI7D1i74g48qplCvg%3D' (2025-07-25)
  → 'github:NixOS/nixpkgs/7b6929d8b900de3142638310f8bc40cff4f2c507?narHash=sha256-S30TWshtDmNlU30u842RidFUraKj1f2dd4nrKRHm3gE%3D' (2025-08-02)

Author: github-actions[bot]