Retain exact recovery after batch start failure

Persist job-ID terminal outcomes before final queue acknowledgement and clear recovery evidence only after both the terminal marker and renderer queue are durable.

lib/upload-recovery.js

@@ -31,6 +31,39 @@
     return Array.from(snapshots.values());
   }
 
+  function buildFailedUploadSummary(tasks, message, now = Date.now()) {
+    const files = new Map();
+    for (const [index, task] of (Array.isArray(tasks) ? tasks : []).entries()) {
+      if (!task || typeof task !== 'object') continue;
+      const filePath = typeof task.file === 'string' ? task.file : '';
+      const fileName = filePath.split(/[\\/]/).pop() || `upload-${index + 1}`;
+      const key = filePath || `${fileName}\0${index}`;
+      if (!files.has(key)) files.set(key, { name: fileName, size: 0, results: [] });
+      files.get(key).results.push({
+        jobId: typeof task.jobId === 'string' ? task.jobId : '',
+        hoster: typeof task.hoster === 'string' ? task.hoster : '',
+        status: 'error',
+        error: message,
+        failureDetails: null,
+        download_url: null,
+        embed_url: null,
+        file_code: null
+      });
+    }
+    const grouped = Array.from(files.values());
+    const failed = grouped.reduce((count, file) => count + file.results.length, 0);
+    return {
+      id: `start-error-${now}`,
+      timestamp: new Date(now).toISOString(),
+      total: failed,
+      succeeded: 0,
+      failed,
+      skipped: 0,
+      files: grouped,
+      error: message
+    };
+  }
+
   function getRecoveryOutcome(job, recovery) {
     const status = typeof job?.status === 'string' ? job.status : 'preview';
     const jobId = typeof job?.id === 'string' ? job.id : '';
@@ -50,5 +83,5 @@
     return { status, interrupted: interruptedIds.has(jobId) && !terminalStatuses.has(status) };
   }
 
-  return { buildTerminalJobSnapshots, getRecoveryOutcome };
+  return { buildFailedUploadSummary, buildTerminalJobSnapshots, getRecoveryOutcome };
 });