Fixes several small issues found during code review:
- fix(xray): return explicit nil instead of stale err in getLogPath
- fix(xray): remove duplicate doc comment on GetErrorLogPath
- refactor: remove unreachable return after log.Fatalf (×4)
- fix(cli): add missing newline to listen IP success message
- fix(cli): typo "form" → "from" in migrate help text
- refactor: simplify var+assign to short declaration for server/subServer
- fix(controller): return error from getTwoFactorEnable instead of swallowing it