feat: add accessible video validation, remove AI confidence check

- Add validation for accessible_video_gcs (file exists, size 0.1MB-5GB)
- Add validation for retimed_captions_vtt_gcs when accessible video exists
- Add AD Videos count to asset validation panel
- Include retimed captions in VTT file count
- Remove AI confidence from validation panel and backend checks

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

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

backend/app/services/validation.py

@@ -58,10 +58,23 @@ class AssetValidationService:
                 if mp3_error:
                     errors.append(mp3_error)
 
-        # Check minimum quality requirements
-        ai_confidence = job_doc.get("ai", {}).get("confidence", 0)
-        if ai_confidence < 0.7:
-            errors.append(f"AI confidence too low: {ai_confidence:.1%} (minimum: 70%)")
+            # Validate accessible video if present
+            if lang_output.get("accessible_video_gcs"):
+                video_error = await AssetValidationService._validate_video_asset(
+                    lang_output.get("accessible_video_gcs"),
+                    f"{language} accessible video"
+                )
+                if video_error:
+                    errors.append(video_error)
+
+                # Validate retimed captions if accessible video uses pause-insert method
+                if lang_output.get("retimed_captions_vtt_gcs"):
+                    retimed_error = await AssetValidationService._validate_vtt_asset(
+                        lang_output.get("retimed_captions_vtt_gcs"),
+                        f"{language} retimed captions VTT"
+                    )
+                    if retimed_error:
+                        errors.append(retimed_error)
 
         return len(errors) == 0, errors
 
@@ -125,6 +138,35 @@ class AssetValidationService:
 
         return None
 
+    @staticmethod
+    async def _validate_video_asset(gcs_uri: str, asset_name: str) -> str | None:
+        """Validate a video asset exists and has reasonable properties"""
+        if not gcs_uri:
+            return f"Missing {asset_name}"
+
+        try:
+            blob_path = gcs_uri.replace(f"gs://{gcs_service.bucket.name}/", "")
+            blob = gcs_service.bucket.blob(blob_path)
+
+            if not blob.exists():
+                return f"{asset_name} file not found in storage"
+
+            # Reload blob to get metadata (including size)
+            blob.reload()
+
+            # Check file size (should be reasonable for video)
+            size_mb = blob.size / (1024 * 1024) if blob.size else 0
+            if size_mb < 0.1:  # Less than 100KB
+                return f"{asset_name} file too small (likely empty or corrupted)"
+            elif size_mb > 5000:  # More than 5GB
+                return f"{asset_name} file too large ({size_mb:.1f}MB)"
+
+        except Exception as e:
+            logger.error(f"Failed to validate {asset_name}: {e}")
+            return f"{asset_name} validation error: {str(e)}"
+
+        return None
+
 
 # Global service instance
 asset_validation_service = AssetValidationService()

frontend/src/routes/admin/FinalDetail.tsx

@@ -240,8 +240,8 @@ export function FinalDetail() {
             <span className="ml-1 font-medium">{_countMp3Files(job.outputs || {})}</span>
           </div>
           <div>
-            <span className={validation?.is_valid ? 'text-green-700' : 'text-red-700'}>AI Confidence:</span>
-            <span className="ml-1 font-medium">{job.ai?.confidence ? `${(job.ai.confidence * 100).toFixed(1)}%` : 'N/A'}</span>
+            <span className={validation?.is_valid ? 'text-green-700' : 'text-red-700'}>AD Videos:</span>
+            <span className="ml-1 font-medium">{_countAccessibleVideos(job.outputs || {})}</span>
           </div>
         </div>
       </div>
@@ -395,10 +395,15 @@ function _countVttFiles(outputs: Record<string, LangOutput>): number {
   Object.values(outputs).forEach(lang => {
     if (lang.captions_vtt_gcs) count++;
     if (lang.ad_vtt_gcs) count++;
+    if (lang.retimed_captions_vtt_gcs) count++;
   });
   return count;
 }
 
 function _countMp3Files(outputs: Record<string, LangOutput>): number {
   return Object.values(outputs).filter(lang => lang.ad_mp3_gcs).length;
+}
+
+function _countAccessibleVideos(outputs: Record<string, LangOutput>): number {
+  return Object.values(outputs).filter(lang => lang.accessible_video_gcs).length;
 }