Add job error persistence and friendly error UI
Backend:
- Migration 0003_job_error: adds error_message and error_code columns to jobs table
- models/job.go: add ErrorMessage, ErrorCode fields to Job struct; SetError method; update all SELECT queries
- models/job_log.go: GetAllFiltered also reads error_message and error_code (via Job embed)
- syncengine/engine.go: setJobError() helper; capture errors at Wol timeout (wol_timeout), rsync error (rsync_error), and exit_code failure points
- api/dto.go: add ErrorMessage and ErrorCode to JobResponse
- api/handlers_jobs.go: jobToResp propagates error fields
Frontend:
- api/client.ts: add error_message? and error_code? to Job interface
- lib/status.ts: add ERROR_CODES map with friendly titles/hints; getErrorCodeInfo()
- components/ErrorDetailsModal.tsx: new modal showing error title, hint, full message, job metadata, and stderr log; copy-all and download-log buttons
- pages/JobDetail.tsx: error banner for failed jobs with title/hint; View error button opens ErrorDetailsModal; SSE updates error_message in real-time
darroyo
9d32ef7fd6