fix(ui): restore original high-score windows

Replace modern overlays with the reconstructed HighScore child and DIALOG 32514 topology, exact DAT993 background, row coordinates, original strings, unpadded scores, and 21-character edit behavior. Restore OK/Cancel semantics, including Escape preserving the prefilled name and allowing an accepted empty name, with deterministic screenshot scenarios.

Test Plan:
- cargo test --all-targets
- cargo clippy --all-targets --all-features -- -D warnings
- rumdl check CHANGELOG.md RECONSTRUCTION.md README.md
- cargo run --quiet -- --simulate highscores --step 0 --screenshot /tmp/tdkpin-highscores.png
- cargo run --quiet -- --simulate name-entry --step 0 --screenshot /tmp/tdkpin-name-entry.png
- git diff --check

tdkpin-rs/src/assets.rs

@@ -8,6 +8,7 @@ pub struct Assets {
     pub inactive_table: Texture2D,
     pub loading: Texture2D,
     pub loading_progress: Texture2D,
+    pub highscore_background: Texture2D,
     pub help: [Texture2D; 5],
     pub media: [Texture2D; 4],
     pub diamond: [Texture2D; 9],
@@ -31,6 +32,7 @@ impl Assets {
         let inactive_table = texture(include_bytes!("../assets/original/images/dat_00998.png"));
         let loading = texture(include_bytes!("../assets/original/images/dat_00995.png"));
         let loading_progress = texture(include_bytes!("../assets/original/images/dat_00994.png"));
+        let highscore_background = texture(include_bytes!("../assets/original/images/dat_00993.png"));
         let help = [
             texture(include_bytes!("../assets/original/images/dat_01001.png")),
             texture(include_bytes!("../assets/original/images/dat_01002.png")),
@@ -149,6 +151,7 @@ impl Assets {
             inactive_table,
             loading,
             loading_progress,
+            highscore_background,
             help,
             media,
             diamond,