flake updates

- remove deleted nixpkgs-stable pin for sops-nix
- remove kernel pin in global modules (defaults to LTS now)
- migrate nerdfonts to new pkgs.nerd-fonts namespace
- disable calibre-server on palatine-hill (for now)
- add SSH_PORT to gitea

Signed-off-by: ahuston-0 <aliceghuston@gmail.com>

modules/boot.nix

@@ -35,7 +35,6 @@ in
   config.boot = lib.mkIf cfg.default {
     supportedFilesystems = [ cfg.filesystem ];
     tmp.useTmpfs = true;
-    kernelPackages = pkgs.linuxPackages_6_10;
     kernelParams =
       [ "nordrand" ]
       ++ lib.optional (cfg.cpuType == "amd") "kvm-amd"