**test(api): add integration tests for API endpoints and core functionality**

- **Integration Tests**:
  - Introduced `api-integration.test.ts` to validate API functionality:
    - Verifies text insertion, vector embedding generation, and search operations.
    - Confirms HNSW index correctness for vector similarity search.
    - Ensures no dimensional mismatches in embeddings.

- **Test Server**:
  - Added test server utilizing Express for endpoint simulation (`/insert` and `/search/text`).

- **Dependencies**:
  - Introduced `express` and `node-fetch` as new dependencies for testing purposes.

- **Vitest Fix**:
  - Updated `vitest.config.ts` to resolve the `process.memoryUsage` error by setting `logHeapUsage: false`.

- **Package Updates**:
  - Modified `package-lock.json` to include newly added dependencies and updates.

**Purpose**: Guarantees the stability of core API endpoints and vector-related functionality, ensuring reliable behavior for end-to-end scenarios.

README.md

@@ -1289,6 +1289,34 @@ terabyte-scale data that can't fit entirely in memory, we provide several approa
 For detailed information on how to scale Brainy for large datasets, see our
 comprehensive [Scaling Strategy](scalingStrategy.md) document.
 
+## Testing
+
+Brainy uses Vitest for testing. The project includes several test scripts:
+
+```bash
+# Run all tests
+npm test
+
+# Run tests with comprehensive reporting
+npm run test:report
+
+# Run tests in watch mode
+npm test:watch
+
+# Run tests with UI
+npm test:ui
+
+# Run specific test suites
+npm run test:node
+npm run test:browser
+npm run test:core
+
+# Run tests with coverage
+npm run test:coverage
+```
+
+The `test:report` script provides a comprehensive test report showing detailed information about all tests that were run, including test names, execution time, and pass/fail status.
+
 ## Contributing
 
 For detailed contribution guidelines, please see [CONTRIBUTING.md](CONTRIBUTING.md).