[ + ] Replaced /mpo test with /mpo simulate — evaluates placeholder resolution using a read-only snapshot of the live cache, leaving the real cache completely unaffected.

[ / ] Fixed redundant cache lookup

[ / ] Fixed unsafe dataSource swap on reload — new MySQL pool is now verified before closing the old one, preventing backend loss if MySQL is temporarily unreachable.

[ / ] Fixed return_value column silently truncating long strings.

[ / ] Fixed PlaceholderAPI fallback potentially being called off the main thread.