fix(studio): refine preset surfaces and repair gallery interactions

packages/design-system/test/recipes.test.ts

@@ -108,3 +108,20 @@ test("mode-dependent recipe values retain mode rules while identical values are
   expect(css).toContain("9px");
   expect(css).not.toContain('[data-theme="light"]');
 });
+
+test("joined component parts keep their authored geometry instead of receiving independent rounding", () => {
+  for (const system of Object.values(CORE_DESIGN_SYSTEMS)) {
+    for (const [name, parts] of Object.entries({
+      StatsBar: ["item", "content"],
+      AuthSplitLayout: ["content"],
+      Collapse: ["trigger", "panel", "content"],
+      InputNumber: ["button", "input", "content"],
+      LayoutSplitter: ["handle"],
+    })) {
+      for (const part of parts) {
+        expect(system.recipes![name]!.base?.[part]?.borderRadius).toBeUndefined();
+        expect(system.recipes![name]!.base?.[part]?.boxShadow).toBeUndefined();
+      }
+    }
+  }
+});