Frontend:
- JobDetail loadLogs: fallback to [] when API returns null
- JobDetail loadJob: pairs ?? [] guard on /api/sync-pairs 500
- JobHistory: Array.isArray guard on job list response
- api client: return undefined for null body instead of throwing
Backend:
- handlers_jobs GetLog: return [] instead of null when no log rows
- router: custom recoverer middleware that logs panics to slog
with full stack trace, method, and path