feat: wire lifecycle hooks into createFetchHttpClient (Closes #409)

[Zhiyilang074811]

Summary

Wires the existing \RequestLifecycleHooks\ interface and \composeHooks\ utility into \createFetchHttpClient, so that \�eforeRequest, \�fterResponse, \onRetry, and \onError\ hooks are actually invoked during real HTTP requests.

Changes

• src/http/fetch-http-client.ts: Added optional \hooks\ parameter to \createFetchHttpClient; invokes \�eforeRequest\ before each request, \�fterResponse\ on 2xx success, \onRetry\ before each retry delay, and \onError\ on all terminal error paths (4xx/5xx, auth failures, timeouts, transport errors)
• tests/lifecycle-hooks-integration.test.ts: Added 4 integration tests covering:
  • \�eforeRequest\ → \�fterResponse\ order on 200
  • \onRetry\ on 429-then-success flow
  • \onError\ on terminal 4xx failure
  • Throwing hooks don't break the request flow

Acceptance Criteria

• Integration test observes \�eforeRequest\ then \�fterResponse\ for a 200 response
• Same setup observes \onRetry\ on 429-then-success and \onError\ on terminal failure
• A throwing hook does not reject the underlying request

Closes #409

[Zhiyilang074811]

Hi! Friendly ping — this PR has been open for a couple of days with all checks passing. Ready for review when you have time. Thanks! 🙏

[Zhiyilang074811]

Hi! Friendly ping — bounty PR (#409) open for ~2 days, all checks passing. Ready for review. Thanks! 🙏