- Strategy 1: scan inline <script> blocks for .m3u8 URLs (skip subtitles/captions)
- Strategy 2: check video element HLS player instances (hlsInstance, _hls)
- Strategy 3: probe common global config objects (hlsConfig, playerConfig, etc.)
- Storage items now include hlsManifest and mediaType fields
- When HLS detected and src is blob:/empty, promote manifest URL to primary
- Backward compatible: direct MP4 entries unaffected