feat: re-export RecordId from crate root

[omerbenamram]

Summary

• Re-export RecordId from the crate root so downstream code can use evtx::RecordId.
• Add an integration test to prevent regressions.

Closes #234.

Test plan

• cargo test -q --test test_record_id_public

---

Note

Re-exports RecordId at the crate root and adds an integration test to ensure it remains public.

• Public API:
  • Re-export RecordId from src/lib.rs to expose evtx::RecordId.
• Tests:
  • Add tests/test_record_id_public.rs to assert RecordId is publicly accessible.

^{Written by Cursor Bugbot for commit f7b01a3. This will update automatically on new commits. Configure here.}