refactor: 重构为多平台多用户架构，全面提升终端体验

- 新增 lib/ 辅助函数（mkNixos/mkDarwin/mkHome），消除硬编码
- 拆分 modules/ 为 nixos/darwin/shared 三层，支持跨平台共享
- 重构 home/ 为 shell/dev/theme 子模块，工具全部迁入用户级
- 深度配置 Tmux/FZF/Atuin/Bat/Eza/Btop/Lazygit/Starship
- 添加 Catppuccin Mocha 统一主题、Nerd Fonts 声明式管理
- 新增 homeConfigurations 输出，支持非 NixOS 系统直装
- 新增 nix-darwin 输入，预留 macOS 扩展路径
- 新增 overlays/ 和 pkgs/ 自定义包基础设施
- 修正 nix-darwin URL（LnL7 → nix-darwin org）

hosts/bare/default.nix

@@ -1,40 +1,16 @@
-{ config, pkgs, ... }:
+{ username, ... }:
 
-let
-  username = "dev"; # ← 修改此处设置用户名
-in
 {
-  # ── 引导 ─────────────────────────────────────────────
+  # ── Boot ─────────────────────────────────────────────
   boot.loader.systemd-boot.enable = true;
   boot.loader.efi.canTouchEfiVariables = true;
 
-  # ── 网络 ─────────────────────────────────────────────
-  networking.hostName = "nixos";
+  # ── Network ──────────────────────────────────────────
   networking.networkmanager.enable = true;
+  users.users.${username}.extraGroups = [ "networkmanager" ];
 
-  # ── 用户 ─────────────────────────────────────────────
-  users.users.${username} = {
-    isNormalUser = true;
-    extraGroups = [
-      "wheel"
-      "docker"
-      "networkmanager"
-    ];
-    shell = pkgs.zsh;
-  };
-
-  # ── Home Manager ─────────────────────────────────────
-  home-manager = {
-    useGlobalPkgs = true;
-    useUserPackages = true;
-    users.${username} = import ../../home;
-  };
-
-  # ── sudo ─────────────────────────────────────────────
-  security.sudo.wheelNeedsPassword = false;
-
-  # ── 硬件 ─────────────────────────────────────────────
-  # 首次安装后生成硬件配置并取消注释：
+  # ── Hardware ─────────────────────────────────────────
+  # After first install, generate and uncomment:
   #   sudo nixos-generate-config --show-hardware-config > hosts/bare/hardware-configuration.nix
   # imports = [ ./hardware-configuration.nix ];
 

hosts/macbook/default.nix

@@ -0,0 +1,11 @@
+{ username, ... }:
+
+{
+  # ── macOS host-specific configuration ────────────────
+  # Uncomment and configure when macOS machine is available.
+
+  # Touch ID for sudo
+  # security.pam.services.sudo_local.touchIdAuth = true;
+
+  # system.stateVersion = 5;
+}

hosts/wsl/default.nix

@@ -1,8 +1,5 @@
-{ config, pkgs, ... }:
+{ username, ... }:
 
-let
-  username = "dev"; # ← 修改此处设置用户名
-in
 {
   # ── WSL ──────────────────────────────────────────────
   wsl = {
@@ -10,27 +7,5 @@ in
     defaultUser = username;
   };
 
-  networking.hostName = "nixos-wsl";
-
-  # ── 用户 ─────────────────────────────────────────────
-  users.users.${username} = {
-    isNormalUser = true;
-    extraGroups = [
-      "wheel"
-      "docker"
-    ];
-    shell = pkgs.zsh;
-  };
-
-  # ── Home Manager ─────────────────────────────────────
-  home-manager = {
-    useGlobalPkgs = true;
-    useUserPackages = true;
-    users.${username} = import ../../home;
-  };
-
-  # ── sudo ─────────────────────────────────────────────
-  security.sudo.wheelNeedsPassword = false;
-
   system.stateVersion = "24.11";
 }