test: expand mocked CLI integration tests to 17 tests

Add comprehensive mocked API tests covering:
- Cloud subscription operations (get, list, create)
- Enterprise database and cluster operations
- HTTP methods (GET, POST, PUT, DELETE)
- Error responses (401, 404, 500)
- Output formats (JSON, YAML)
- JMESPath query filtering
- Async operation task IDs
- Multiple requests to same mock server
- Verbose logging flag

All tests use wiremock to verify request construction without
hitting real APIs. Tests validate auth headers, request bodies,
and response handling.

Author: joshrotenberg