feat(hooks): add useApiMutation hook for API write flows (#301)

[mysterio123865]

Closes #301

Summary

Implements Issue #301 by introducing a reusable useApiMutation hook to simplify and standardize API mutation handling across the application.

Changes

• Added src/lib/useApiMutation.ts

  • Exposes mutate, status, error, and reset
  • Handles request cancellation on component unmount or mutation supersession
  • Prevents stale responses from updating state after cancellation

• Added comprehensive tests:

  • src/lib/__tests__/useApiMutation.test.tsx
  • 14 tests covering mutation states, cancellation behavior, error handling, reset flow, and edge cases
  • Achieved ~97% branch coverage

• Migrated src/app/services/new/page.tsx to use the new mutation hook

• Added documentation:

  • Updated docs/hooks.md with usage details and examples

Validation

✅ Lint passed on changed files
✅ Related tests passed (29 tests)
✅ npm run build completed successfully

Note: The full test suite still reports existing failures in api-keys/page.test.tsx, which are already present on the main branch and are unrelated to this change.

Tracking

Closes #301

Commit

feat(hooks): add useApiMutation for write flows

[mikewheeleer]

solid PR @mysterio123865 — clear diff, good coverage. merging 🙌