feat(frontend): register schema-linking widget + response summary

frontend/src/shell/WidgetHost.tsx

@@ -29,7 +29,10 @@ export function WidgetHost({ sessionId }: { sessionId: string | null }) {
     }
     setLastUserEntry({
       kind: "choice",
-      text: r.text ?? r.choices?.join(", ") ?? r.decision?.type ?? r.control ?? "(choice)",
+      text:
+        r.kind === "schema-linking"
+          ? `${r.tables?.filter((t) => t.enacted).length ?? 0} tables curated`
+          : r.text ?? r.choices?.join(", ") ?? r.decision?.type ?? r.control ?? "(choice)",
     });
     clearPending();
   };

frontend/src/widgets/index.ts

@@ -5,10 +5,12 @@ import { FreetextWidget } from "./FreetextWidget";
 import { MultiselectWidget } from "./MultiselectWidget";
 import { ArtifactGateWidget } from "./ArtifactGateWidget";
 import { ArtifactWidget } from "./ArtifactWidget";
+import { SchemaLinkingGateWidget } from "./SchemaLinkingGateWidget";
 register("select", SelectWidget);
 register("info", InfoWidget);
 register("freetext", FreetextWidget);
 register("multiselect", MultiselectWidget);
 register("artifact-gate", ArtifactGateWidget);
 register("artifact", ArtifactWidget);
+register("schema-linking", SchemaLinkingGateWidget);
 export { resolve } from "./registry";

frontend/src/widgets/registry.test.tsx

@@ -13,3 +13,9 @@ test("resolve falls back for unknown kind and shows the JSON", () => {
   render(<Comp descriptor={{ id: "u1", widget: "totally-unknown", title: "X" } as any} onRespond={() => {}} />);
   expect(screen.getByText(/Unsupported widget/i)).toBeInTheDocument();
 });
+
+test("index registers the schema-linking widget", async () => {
+  await import("./index");
+  const Comp = resolve("schema-linking");
+  expect(Comp.name).toBe("SchemaLinkingGateWidget");
+});