test(fmdapi): add mock infrastructure for unit tests (#102)

- Create capture script for recording live API responses
- Add mock-fetch utility for mocking global fetch in tests
- Reorganize tests: move E2E tests to tests/e2e/
- Create mock-based unit tests that don't require live FM server
- Update vitest config to exclude E2E tests by default
- Add test:e2e and capture scripts to package.json

Co-Authored-By: Claude Opus 4.5 <[email protected]>

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Builds a robust test setup that decouples unit tests from a live FileMaker server and isolates E2E tests.
> 
> - **Mock infra**: Add `tests/utils/mock-fetch.ts`, `tests/fixtures/responses.ts` (captured FM responses), and `tests/utils/mock-server-url.ts`; refactor unit tests to stub global `fetch` and use `mockResponses`
> - **Capture script**: New `scripts/capture-responses.ts` to hit a live server, sanitize URLs, and regenerate `tests/fixtures/responses.ts`
> - **Test reorg**: Move live tests to `tests/e2e/**` and add new E2E specs; convert existing `client-methods.test.ts` to pure unit tests using mocks
> - **Config/scripts**: Update `package.json` with `test:e2e` and `capture` commands and simplify `test`; adjust `vitest.config.ts` to exclude `tests/e2e/**` by default
> - Minor test cleanups: consistent imports (`../src/index`), afterEach `vi.unstubAllGlobals()`, and small assertion/name fixes
> 
> <sup>Written by [Cursor Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit beec7bf. This will update automatically on new commits. Configure [here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: eluce2

packages/fmdapi/package.json

@@ -44,7 +44,9 @@
     "format": "biome format --write .",
     "dev": "tsc --watch",
     "ci": "pnpm build && pnpm check-format && pnpm publint --strict && pnpm test",
-    "test": "doppler run -- vitest run",
+    "test": "vitest run",
+    "test:e2e": "doppler run -- vitest run tests/e2e",
+    "capture": "doppler run -- npx tsx scripts/capture-responses.ts",
     "typecheck": "tsc --noEmit",
     "changeset": "changeset",
     "release": "pnpm build && changeset publish --access public",