7786871d6c
Backend: - Add infer crate for magic-byte MIME detection (<1μs per file) - New src/common/mime_detect.rs: refine_content_type() with priority magic bytes > extension > client Content-Type - Inject MIME refinement in file upload handler (after spool to temp) - Inject MIME refinement in chunked upload handler (after assembly) Frontend: - Extend isViewableFile() to include audio/* and video/* - Add createMediaViewer() to InlineViewer with <audio>/<video> controls - Blob URL pattern for authenticated streaming playback - Graceful fallback for unsupported codecs (error message + download) - CSS: video player, audio wrapper with animated icon, responsive