fix(mindspace): map publication RPC errors to HTTP status codes

Return 404/401/403 from MindSpace RPC for known publication errors and
preserve error codes through the Portal remote adapter.

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

mindspace-service/mindspace-rpc-server.test.mjs

@@ -196,3 +196,52 @@ test('rpc invocation revives JSON-serialized buffers before dispatch', async ()
   assert.deepEqual(response.body, { isBuffer: true, size: payload.length });
   assert.equal(Buffer.isBuffer(adapter.calls.writeUploadContent[0][2]), true);
 });
+
+test('rpc maps publication_not_found to 404 with error code', async () => {
+  const adapter = createStubAdapter();
+  adapter.publicationService.resolvePublic = async () => {
+    const error = new Error('公开页面不存在');
+    error.code = 'publication_not_found';
+    throw error;
+  };
+  const handler = await createMindSpaceRpcRequestHandler({
+    adapter,
+    env: {
+      MINDSPACE_MEMIND_ROOT: '..',
+    },
+  });
+
+  const response = await runRequest(handler, {
+    method: 'POST',
+    path: '/mindspace/v1/adapter/publicationService/resolvePublic',
+    body: JSON.stringify({ args: ['john', 'missing-page', null, null, {}] }),
+  });
+
+  assert.equal(response.statusCode, 404);
+  assert.equal(response.body.code, 'publication_not_found');
+  assert.match(response.body.message, /公开页面不存在/);
+});
+
+test('rpc maps publication_login_required to 401 with error code', async () => {
+  const adapter = createStubAdapter();
+  adapter.publicationService.resolvePublic = async () => {
+    const error = new Error('登录后才能访问此页面');
+    error.code = 'publication_login_required';
+    throw error;
+  };
+  const handler = await createMindSpaceRpcRequestHandler({
+    adapter,
+    env: {
+      MINDSPACE_MEMIND_ROOT: '..',
+    },
+  });
+
+  const response = await runRequest(handler, {
+    method: 'POST',
+    path: '/mindspace/v1/adapter/publicationService/resolvePublic',
+    body: JSON.stringify({ args: ['john', 'login-page', null, null, {}] }),
+  });
+
+  assert.equal(response.statusCode, 401);
+  assert.equal(response.body.code, 'publication_login_required');
+});