fix: name the frame's damage

cce-ui@3386087 added Frame2D::damage, and this crate's pin includes it, so
it did not build. None is the documented default: a full frame, which is
what the lock screen always paints.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

 src/main.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/main.rs b/src/main.rs
index d5238c6..7c1dbf2 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -284,6 +284,8 @@ impl AppState {
             images: &images,
             plate_features: &features,
             clear_color: [0.0, 0.0, 0.0, 1.0],
+            // Always a full frame: the lock screen repaints whole.
+            damage: None,
         });
     }