fix: make base modules enabled by default; document lazylib→lazygit

- All base/* modules now use (mkEnableOption "...") // { default = true; }
  so they activate automatically when imported — no explicit .enable = true
  required in host configs
- packages.nix: add comment documenting that lazylib does not exist in
  nixpkgs; lazygit is the correct and intended package
- zellij-ps.nix: clarify that cli.zellij-ps namespace is intentional —
  it is the home-manager module convention from m3ta-nixpkgs
- nix flake check passes (warnings are pre-existing)

home/base/cli-tools/zellij-ps.nix

@@ -1,5 +1,7 @@
 # Zellij-ps — project-aware Zellij session manager from m3ta-nixpkgs.
-# Delegates to the cli.zellij-ps module provided by inputs.m3ta-nixpkgs.
+# Delegates to `cli.zellij-ps` — the home-manager module namespace provided by
+# m3ta-nixpkgs (inputs.m3ta-nixpkgs.nixosModules.default). This is intentional;
+# `cli.*` is the convention used by m3ta-nixpkgs home-manager modules.
 {
   config,
   lib,
@@ -9,7 +11,8 @@ with lib; let
   cfg = config.base.cliTools.zellijPs;
 in {
   options.base.cliTools.zellijPs = {
-    enable = mkEnableOption "enable zellij-ps project session manager";
+    # Enabled by default — base modules are always-on.
+    enable = (mkEnableOption "enable zellij-ps project session manager") // {default = true;};
 
     projectFolders = mkOption {
       type = types.listOf types.path;