fix: update AI Mailer configuration, adjust polling interval, and modify logging level

feat: update NixOS channel to 25.05 and remove unused unstable imports
fix: correct keyboard layout configuration in sway
feat: update ai-mailer package source and hash

hosts/nb/modules/coding.nix

@@ -1,10 +1,10 @@
 { config, pkgs, ... }:
 let
-  unstable = import (fetchTarball https://nixos.org/channels/nixos-unstable/nixexprs.tar.xz) {
-    config = { allowUnfree = true; };
-  };
+  # unstable = import (fetchTarball https://nixos.org/channels/nixos-unstable/nixexprs.tar.xz) {
+  #   config = { allowUnfree = true; };
+  # };
 in {
   environment.systemPackages = with pkgs; [
-    unstable.claude-code
+    claude-code
   ];
 }