feat(backend): add foundation services and sql idempotency

backend/core-api/test/app.test.js

@@ -0,0 +1,61 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import request from 'supertest';
+import { createApp } from '../src/app.js';
+
+process.env.AUTH_BYPASS = 'true';
+process.env.LLM_MOCK = 'true';
+
+test('GET /healthz returns healthy response', async () => {
+  const app = createApp();
+  const res = await request(app).get('/healthz');
+
+  assert.equal(res.status, 200);
+  assert.equal(res.body.ok, true);
+  assert.equal(typeof res.body.requestId, 'string');
+  assert.equal(typeof res.headers['x-request-id'], 'string');
+});
+
+test('POST /core/create-signed-url requires auth', async () => {
+  process.env.AUTH_BYPASS = 'false';
+  const app = createApp();
+  const res = await request(app).post('/core/create-signed-url').send({
+    fileUri: 'gs://krow-workforce-dev-private/foo.pdf',
+  });
+
+  assert.equal(res.status, 401);
+  assert.equal(res.body.code, 'UNAUTHENTICATED');
+  process.env.AUTH_BYPASS = 'true';
+});
+
+test('POST /core/create-signed-url returns signed URL', async () => {
+  const app = createApp();
+  const res = await request(app)
+    .post('/core/create-signed-url')
+    .set('Authorization', 'Bearer test-token')
+    .send({
+      fileUri: 'gs://krow-workforce-dev-private/foo.pdf',
+      expiresInSeconds: 300,
+    });
+
+  assert.equal(res.status, 200);
+  assert.equal(typeof res.body.signedUrl, 'string');
+  assert.equal(typeof res.body.expiresAt, 'string');
+  assert.equal(typeof res.body.requestId, 'string');
+});
+
+test('POST /invokeLLM legacy alias works', async () => {
+  const app = createApp();
+  const res = await request(app)
+    .post('/invokeLLM')
+    .set('Authorization', 'Bearer test-token')
+    .send({
+      prompt: 'hello',
+      responseJsonSchema: { type: 'object' },
+      fileUrls: [],
+    });
+
+  assert.equal(res.status, 200);
+  assert.equal(typeof res.body.result, 'object');
+  assert.equal(typeof res.body.model, 'string');
+});