fix: handle missing job logs

[kuntal1461]

Summary

• Fixes [ultra-review] outputJobLog crashes when a job log is missing #1192.
• Prevent outputJobLog from crashing when a terminal job has no log.
• Add regression coverage for missing, empty, and valid terminal job logs.

Tests

• CI=true pnpm exec vitest run test/local/lib/utils.test.ts
• CI=true pnpm run test:local
• CI=true pnpm run lint
• CI=true pnpm run format
• CI=true pnpm run build