feat(shell): add tmux

shell/tmux.nix

@@ -0,0 +1,28 @@
+{pkgs, ...}: {
+  programs = {
+    tmux = {
+      enable = true;
+      clock24 = true;
+      keyMode = "vi";
+      escapeTime = 0;
+      plugins = with pkgs.tmuxPlugins; [
+        tmux-colors-solarized
+        vim-tmux-navigator
+        {
+          plugin = power-theme;
+          extraConfig = ''
+            set -g @tmux_power_theme "colour4"
+          '';
+        }
+      ];
+      terminal = "xterm-256color";
+      extraConfig = ''
+        # Terminal overrides
+        set-option -sa terminal-overrides ",xterm-256color:Tc"
+
+        # Reload tmux config to ensure theme is applied
+        bind r source-file ~/.config/tmux/tmux.conf \; display-message "Config reloaded!"
+      '';
+    };
+  };
+}