fix: 修复 nix flake check 和 build 错误

- 添加 system.primaryUser (nix-darwin 新要求)
- 全局应用 overlays 解决 comment-checker 找不到的问题
- git/ssh/delta 选项迁移到 home-manager 新 API
- 包改名: dockerfile-language-server, nixfmt, nixd
- neovim withRuby=false, catppuccin homeModules 更名
- 更新 flake.lock (nixpkgs, home-manager, catppuccin)

home/dev/neovim.nix

@@ -1,4 +1,4 @@
-{ pkgs, ... }:
+{ ... }:
 
 {
   programs.neovim = {
@@ -8,17 +8,6 @@
     vimAlias = true;
     withNodeJs = true;
     withPython3 = true;
+    withRuby = false;
   };
-
-  # ── Neovim distro configuration ──
-  # Option A: LazyVim / NvChad / AstroNvim via xdg.configFile
-  #   xdg.configFile."nvim" = {
-  #     source = ./nvim-config;
-  #     recursive = true;
-  #   };
-  #
-  # Option B: NixVim (fully declarative)
-  #   Add to flake.nix inputs:
-  #     nixvim.url = "github:nix-community/nixvim";
-  #   Then configure here.
 }