Add comprehensive zsh configuration with Powerlevel10k

- Create separate zsh.nix module for enhanced shell experience
- Add Powerlevel10k theme with custom configuration from wizard
- Include useful aliases for git, nix, and navigation commands
- Add modern CLI tools: fzf, fd, ripgrep, bat for better productivity
- Enable autosuggestions, syntax highlighting, and completion
- Add portable p10k.zsh configuration for consistent prompt across machines
- Update flake.nix to import zsh module and remove inline config
- Update tmux.nix with prefix indicator and datetime removal

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

zsh.nix

@@ -0,0 +1,64 @@
+{ pkgs, ... }:
+
+{
+  programs.zsh = {
+    enable = true;
+    defaultKeymap = "viins";
+    enableVteIntegration = true;
+    enableCompletion = true;
+    autosuggestion.enable = true;
+    syntaxHighlighting.enable = true;
+    
+    sessionVariables = {
+      COLORTERM = "truecolor";
+      EDITOR = "nvim";
+    };
+    
+    shellAliases = {
+      ll = "ls -alF";
+      la = "ls -A";
+      l = "ls -CF";
+      ".." = "cd ..";
+      "..." = "cd ../..";
+      
+      # Git aliases
+      gs = "git status";
+      ga = "git add";
+      gc = "git commit";
+      gp = "git push";
+      gl = "git pull";
+      gd = "git diff";
+      
+      # Nix helpers
+      hm = "home-manager";
+      hms = "home-manager switch --flake ~/.config/nix#yanlin";
+    };
+    
+    initExtra = ''
+      # Load Powerlevel10k theme
+      if [[ -f ${pkgs.zsh-powerlevel10k}/share/zsh-powerlevel10k/powerlevel10k.zsh-theme ]]; then
+        source ${pkgs.zsh-powerlevel10k}/share/zsh-powerlevel10k/powerlevel10k.zsh-theme
+      fi
+      
+      # Load Powerlevel10k configuration (managed by Nix)
+      source ~/.p10k.zsh
+    '';
+  };
+  
+  # Essential packages for enhanced zsh experience
+  home.packages = with pkgs; [
+    zsh-powerlevel10k
+    fzf
+    fd
+    ripgrep
+    bat
+  ];
+  
+  programs.fzf = {
+    enable = true;
+    enableZshIntegration = true;
+  };
+  
+  # Manage Powerlevel10k configuration
+  home.file.".p10k.zsh".source = ./p10k.zsh;
+}