feat(uwf-agent): Phase 1 agent returns output and detailHash

- Change AgentRunFn to return { output, detailHash } instead of raw string

- Remove agent-kit detail CAS write; agents store their own detail nodes

- Hermes stores raw output as typed hermes-raw-output CAS node

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/mock-agent.ts

@@ -1,11 +1,31 @@
 #!/usr/bin/env bun
 // Mock agent for smoke testing
-import { createAgent } from "../packages/uwf-agent-kit/src/index.js";
+import { bootstrap, type JSONSchema, putSchema } from "@uncaged/json-cas";
+import {
+  createAgent,
+  createAgentStore,
+  resolveStorageRoot,
+} from "../packages/uwf-agent-kit/src/index.js";
+
+const MOCK_RAW_OUTPUT_SCHEMA: JSONSchema = {
+  title: "mock-raw-output",
+  type: "object",
+  required: ["text"],
+  properties: {
+    text: { type: "string" },
+  },
+  additionalProperties: false,
+};
 
 const agent = createAgent({
   name: "mock",
   run: async (ctx) => {
-    return `Mock output for role ${ctx.role}: task was "${ctx.prompt}"`;
+    const output = `Mock output for role ${ctx.role}: task was "${ctx.prompt}"`;
+    const { store } = await createAgentStore(resolveStorageRoot());
+    await bootstrap(store);
+    const schemaHash = await putSchema(store, MOCK_RAW_OUTPUT_SCHEMA);
+    const detailHash = await store.put(schemaHash, { text: output });
+    return { output, detailHash };
   },
 });