key: add TODO's for media keys

Add TODO comments in places where we need to add media keys.

src/apprt/gtk/key.zig

@@ -211,4 +211,6 @@ const keymap: []const RawEntry = &.{
     .{ c.GDK_KEY_Control_R, .right_control },
     .{ c.GDK_KEY_Alt_R, .right_alt },
     .{ c.GDK_KEY_Super_R, .right_super },
+
+    // TODO: media keys
 };

src/input/key.zig

@@ -357,6 +357,8 @@ pub const Key = enum(c_int) {
     kp_delete,
     kp_begin,
 
+    // TODO: media keys
+
     // modifiers
     left_shift,
     left_control,

src/input/kitty.zig

@@ -117,6 +117,8 @@ const raw_entries: []const RawEntry = &.{
     .{ .kp_delete, 57426, 'u', false },
     .{ .kp_begin, 57427, 'u', false },
 
+    // TODO: media keys
+
     .{ .left_shift, 57441, 'u', true },
     .{ .right_shift, 57447, 'u', true },
     .{ .left_control, 57442, 'u', true },