Add scan_datastore_storage() to walk DATASTORE_PATH and categorize media by directory structure (movies/series/anime/kdrama/downloads/other) with size/file counts. Add raid_status() to parse /proc/mdstat and mdadm --detail for RAID level, active/failed devices, and recovery progress. Add /api/datastore endpoint with 15-minute cache for storage scans and live RAID updates. Install mdadm/util-linux/