feat(wezterm): Add Wezterm config

This config does require the user to format their configuration in a
specific way:
```lua
local config = wezterm.config_builder()

-- config here...

return config
```

Since this is the format that the official documentation uses in
examples, most users probably follow suit. But worth pointing out
regardless.

modules/home-manager/wezterm.nix

@@ -0,0 +1,15 @@
+{ config, lib, ... }:
+let
+  cfg = config.programs.wezterm.rose-pine;
+  enable = cfg.enable && config.programs.wezterm.enable;
+in
+{
+  options.programs.wezterm.rose-pine = lib.rp.mkRosePineOpt { name = "wezterm"; };
+
+  config.programs.wezterm.extraConfig = lib.mkIf enable ''
+    local theme = wezterm.plugin.require('https://github.com/neapsix/wezterm').${cfg.flavor}
+
+    config.colors = theme.colors()
+    config.window_frame = theme.window_frame()
+  '';
+}