Fix Windows service premature exit and stop timeout in service.c

- Add retry logic (3 retries × 2s) in serviceMain before declaring server
  stopped to avoid false negatives from transient lock file check failures
- Increase doStopApplication nTries from 10 to 30 for heavier loaded servers

Agent-Logs-Url: https://github.com/OpenIdentityPlatform/OpenDJ/sessions/b618397b-6f5a-4c9b-8bec-3bb14df3e3e3

Co-authored-by: vharseko <6818498+vharseko@users.noreply.github.com>