Optimize unit tests: nip05.spec.ts & nip03.spec.ts (network)

[phoenix-server]

Both nip05.spec.ts (42 tests) and nip03.spec.ts (34 tests) perform HTTP/network operations:

• Network calls even when mocked
• Promise/async overhead
• Timeout handling

These 76 combined tests are slow due to network I/O. Goal: Reduce execution time by at least 25% through improved mocking and test consolidation.