feat: auto-use cached HQ video file without upgrade prompt

Co-authored-by: Cursor <cursoragent@cursor.com>

src/lib/stores/videoSession.svelte.ts

@@ -262,6 +262,22 @@ export async function beginDownload() {
 
   session.processingStep = 'downloading';
 
+  // --- Check export (HQ) cache first ---
+  const exportCached = await checkCachedDownload(session.title, 'export').catch(() => null);
+  if (exportCached) {
+    // HQ file already on disk — use it directly, skip preview entirely
+    session.exportFilePath = exportCached;
+    session.exportProgress = 1.0;
+    session.exportStatus = 'complete';
+    session.previewFilePath = exportCached;
+    session.previewProgress = 1.0;
+    session.previewStatus = 'complete';
+    session.activeVideoPath = exportCached;
+    // No upgrade toast — we're already at best quality
+    triggerPostDownloadProcessing(exportCached);
+    return;
+  }
+
   // --- Preview download (low-res, fast) ---
   const previewCached = await checkCachedDownload(session.title, 'preview').catch(() => null);
   if (previewCached) {
@@ -305,20 +321,11 @@ export async function beginDownload() {
   }
 
   // --- Export download (best quality, background) ---
-  const exportCached = await checkCachedDownload(session.title, 'export').catch(() => null);
-  if (exportCached) {
-    session.exportFilePath = exportCached;
-    session.exportProgress = 1.0;
-    session.exportStatus = 'complete';
-    if ((session.processingStep as ProcessingStep) === 'done') {
-      session.showUpgradeToast = true;
-    }
-  } else {
+  // Only start if not already cached (we handled cached case above with early return)
   session.exportStatus = 'downloading';
   session.exportProgress = 0;
   session.exportFilePath = null;
 
-    // Fire-and-forget — runs in background
   runDownload(
     session.url,
     EXPORT_FORMAT,
@@ -345,5 +352,4 @@ export async function beginDownload() {
     session.exportStatus = 'failed';
     console.error('Export download failed:', e);
   });
-  }
 }