Adds get_database_info and vacuum_database Tauri commands. The General
section now shows current DB size and reclaimable space on load, with a
Compact now button that runs PRAGMA wal_checkpoint(FULL) + VACUUM and
reports how many MB were freed. Button disables automatically when the
database is already compact (< 0.5 MB reclaimable).
LyAhn
d1eb75a4f5