app/internal/wm: change Options fields from values to pointers

Switching to pointer values in Options, including using window manager defaults for size and title, in preparation for updating options on the fly.

Signed-off-by: pierre <pierre.curto@gmail.com>

app/internal/wm/os_js.go

@@ -82,7 +82,9 @@ func NewWindow(win Callbacks, opts *Options) error {
 	})
 	w.addEventListeners()
 	w.addHistory()
-	w.windowMode(opts.WindowMode)
+	if o := opts.WindowMode; o != nil {
+		w.windowMode(*o)
+	}
 	w.w = win
 
 	go func() {