flake.lock: Update

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/6df24922a1400241dae323af55f30e4318a6ca65?narHash=sha256-dklw3AXr3OGO4/XT1Tu3Xz9n/we8GctZZ75ZWVqAVhk%3D' (2025-01-02)
  → 'github:NixOS/nixpkgs/bffc22eb12172e6db3c5dde9e3e5628f8e3e7912?narHash=sha256-8YVQ9ZbSfuUk2bUf2KRj60NRraLPKPS0Q4QFTbc%2Bc2c%3D' (2025-01-08)
• Updated input 'oxalica-rust':
    'github:oxalica/rust-overlay/d40e15e076bcedc5bf5498a0f8ff5f18de4bf8c3?narHash=sha256-vbkoQTInunSjwx9DKebbCNBq9bim8CRj1VbS4eiABfg%3D' (2025-01-04)
  → 'github:oxalica/rust-overlay/06871d5c5f78b0ae846c5758702531b4cabfab9b?narHash=sha256-it8mU8UkbaeVup7GpCI6n2cWPJ/O4U980CxKAMKUGF0%3D' (2025-01-11)
• Updated input 'oxalica-rust/nixpkgs':
    'github:NixOS/nixpkgs/b69de56fac8c2b6f8fd27f2eca01dcda8e0a4221?narHash=sha256-f0SBJz1eZ2yOuKUr5CA9BHULGXVSn6miBuUWdTyhUhU%3D' (2024-10-10)
  → 'github:NixOS/nixpkgs/4bc9c909d9ac828a039f288cf872d16d38185db8?narHash=sha256-nIYdTAiKIGnFNugbomgBJR%2BXv5F1ZQU%2BHfaBqJKroC0%3D' (2025-01-08)