2710

Added

• Game Match Source Tracking — PVGame now tracks how its metadata was sourced (matchSource: none/md5/nameLookup/userImported/manual), which fields the user has customized (userCustomizedFields bitmask), and when the last metadata lookup occurred (lastMetadataLookupDate).
• Preserve-User-Edits Merge Policy — ROMMetadata.merged(with:preserving:) allows callers to protect user-customized fields from being overwritten during automatic metadata re-lookup.