[codex] Make Windows mpv shortcut self-contained (#40)

launcher/config/cli-parser-builder.ts

@@ -43,7 +43,10 @@ export interface CliInvocations {
 
 function applyRootOptions(program: Command): void {
   program
-    .option('-b, --backend <backend>', 'Display backend')
+    .option(
+      '-b, --backend <backend>',
+      'Display backend (auto, hyprland, sway, x11, macos, windows)',
+    )
     .option('-d, --directory <dir>', 'Directory to browse')
     .option('-a, --args <args>', 'Pass arguments to MPV')
     .option('-r, --recursive', 'Search directories recursively')