add pipeline job management with /jobs pages and per-step output viewer

- Pipeline jobs now persist to DB with progress tracking and cost accumulation
- Jobs survive WebSocket disconnects with in-memory event buffer replay
- New /jobs list page with search, status badges, and cost display
- New /jobs/:id detail page with live WebSocket attachment and REST fallback
- Two-column layout using WorkspaceLayout for resizable steps/output panels
- Streaming messages tagged with stepIndex/iterationLabel for per-step output grouping
- TaskRunnerModal links to job detail page once job is created
- Dock entry added for Jobs page

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/server.tsx

@@ -323,6 +323,10 @@ try {
 import { initQueue, enqueueJob as queueEnqueue, cancelJob as queueCancel, listAllJobs as queueList, readJob as queueGet } from './servers/queue/init';
 initQueue().catch((err) => console.error('[queue] failed to initialize:', err));
 
+// Mark any orphaned pipeline jobs from previous server run
+import { cleanupOnStartup } from './servers/api/tasks/pipeline-job-manager';
+cleanupOnStartup().catch((err) => console.error('[pipeline-jobs] startup cleanup failed:', err));
+
 // Ensure PulseAudio is running with virtual sink for cliamp audio streaming
 (async () => {
   const pulseaudio = Bun.which('pulseaudio');