Fusion textures: test continuous defaults

Co-Authored-By: Claude Opus 5.5 <[email protected]>

crates/horizon-optifine/src/fusion/texture.rs

@@ -369,6 +369,13 @@ mod tests {
                 per_tile_animation: false,
             }
         );
+        assert_eq!(
+            meta(r#"{"fusion": {"type": "continuous"}}"#).kind,
+            Kind::Continuous {
+                columns: 1,
+                rows: 1
+            }
+        );
         assert_eq!(
             meta(r#"{"fusion": {"type": "scrolling"}}"#).kind,
             Kind::Scrolling(Scrolling {