Extract duplicated configuration from gunter and magicman into shared system modules. This eliminates ~116 lines of duplication and fixes a malformed gdm.wayland config in magicman. New shared modules: - boot.nix: systemd-boot, EFI, common kernel params - networking.nix: NetworkManager, nftables, firewall base - hyprland.nix: System-level Hyprland and display manager - xdg.nix: XDG session variables and portal setup - nix-config.nix: Nix daemon settings, binary caches, trusted users - nixpkgs-config.nix: allowUnfree and kernel packages default Updated modules: - locale.nix: Added timezone configuration Benefits: - Reduces duplication: net reduction of 53 lines - Magicman gains custom cache substituters for faster builds - Fixes malformed gdm.wayland config in magicman - Both hosts use identical base configuration - Host-specific config clearly stands out Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>