Fix stuck processing jobs and increase timeouts

Background Job Processor:
- Add src/services/jobProcessor.ts that polls RunPod every 30s for stuck jobs
- Automatically completes or fails jobs that were abandoned (user navigated away)
- Times out jobs after 25 minutes

Client-Side Resume:
- Add GET /api/generate/pending endpoint to fetch user's processing jobs
- Add checkPendingJobs() that runs on login/page load
- Show notification banner when user has jobs generating in background
- Add "View Progress" button to resume polling for a job

Timeout Increases (10min → 25min):
- src/utils/validators.ts: request validation max/default
- src/config.ts: RUNPOD_MAX_TIMEOUT_MS default
- public/js/app.js: client-side polling maxTime
- src/services/jobProcessor.ts: background processor timeout

CI/CD Optimization:
- Add paths-ignore to backend build.yaml to skip rebuilds on frontend-only changes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/public/js/app.js

@@ -75,6 +75,62 @@ function showMainApp() {
     }
 
     showSection('generate');
+    checkPendingJobs();
+}
+
+// Pending Jobs
+async function checkPendingJobs() {
+    try {
+        const data = await api('/generate/pending');
+        if (data.jobs && data.jobs.length > 0) {
+            showPendingJobsNotification(data.jobs);
+        }
+    } catch (error) {
+        console.error('Failed to check pending jobs:', error);
+    }
+}
+
+function showPendingJobsNotification(jobs) {
+    // Remove existing banner if any
+    const existingBanner = document.querySelector('.pending-jobs-banner');
+    if (existingBanner) existingBanner.remove();
+
+    const banner = document.createElement('div');
+    banner.className = 'pending-jobs-banner';
+    banner.innerHTML = `
+        <span>You have ${jobs.length} video${jobs.length > 1 ? 's' : ''} generating in the background</span>
+        <div class="pending-jobs-actions">
+            <button class="btn btn-sm" onclick="resumeLatestJob(${jobs[0].id}, '${jobs[0].runpod_job_id}')">View Progress</button>
+            <button class="btn btn-sm" onclick="this.closest('.pending-jobs-banner').remove()">Dismiss</button>
+        </div>
+    `;
+    document.querySelector('.main-content').prepend(banner);
+}
+
+async function resumeLatestJob(contentId, jobId) {
+    // Switch to generate tab and show progress
+    showSection('generate');
+
+    const statusEl = document.getElementById('generation-status');
+    const videoEl = document.getElementById('output-video');
+    const btn = document.getElementById('generate-btn');
+
+    btn.disabled = true;
+    btn.textContent = 'Generating...';
+    statusEl.className = 'status-message info';
+    statusEl.textContent = 'Resuming job...';
+    statusEl.classList.remove('hidden');
+    videoEl.classList.add('hidden');
+
+    // Remove the banner
+    const banner = document.querySelector('.pending-jobs-banner');
+    if (banner) banner.remove();
+
+    // Poll for completion
+    await pollJob(jobId, contentId, statusEl, videoEl);
+
+    btn.disabled = false;
+    btn.textContent = 'Generate Video';
 }
 
 // Login
@@ -268,7 +324,7 @@ document.getElementById('generate-form').addEventListener('submit', async (e) =>
 
 async function pollJob(jobId, contentId, statusEl, videoEl) {
     const startTime = Date.now();
-    const maxTime = 10 * 60 * 1000; // 10 minutes
+    const maxTime = 25 * 60 * 1000; // 25 minutes
 
     while (Date.now() - startTime < maxTime) {
         const elapsed = Math.floor((Date.now() - startTime) / 1000);