fix: scan main frame only, deep-probe HLS, always store mediaType/hlsManifest

- Run scrapeFn in main frame only to avoid iframe noise (23 thumbnails)
- Deep-walk player objects up to depth 5 for .m3u8 URLs
- Always include mediaType and hlsManifest in stored items
- When blob URL detected, substitute with HLS manifest from probe
- Add integration tests for storage pipeline and viewer rendering
- Add eslintignore for dist/

.eslintignore

@@ -0,0 +1 @@
+dist/