Switch the preview overlay from a still <img> to a <video> tag when the focused photo's Type is "video". Uses PhotoPrism's /api/v1/videos/:hash endpoint with the existing previewToken, falls back to a still thumb as the poster, and autoplays muted so the controls reveal without clobbering whatever else is on the page. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>