Decouple core Yaak logic from Tauri (#354)

crates/yaak-models/migrations/20250507140702_remove-ev-sync-states.sql

@@ -0,0 +1,11 @@
+-- There used to be sync code that skipped over environments because we didn't
+-- want to sync potentially insecure data. With encryption, it is now possible
+-- to sync environments securely. However, there were already sync states in the
+-- DB that marked environments as "Synced". Running the sync code on these envs
+-- would mark them as deleted by FS (exist in SyncState but not on FS).
+--
+-- To undo this mess, we have this migration to delete all environment-related
+-- sync states so we can sync from a clean slate.
+DELETE
+FROM sync_states
+WHERE model_id LIKE 'ev_%';