feat(js-core): Typing for MigrateFunction and 'VersionedObject' are…

… available from the package root

projects/js-core/src/public-api.ts

@@ -8,7 +8,11 @@ export * from './lib/predicates';
 export * from './lib/sets';
 export * from './lib/time';
 export { assert } from './lib/assert';
-export { MigrationManager } from './lib/migration-manager';
+export {
+  MigrateFunction,
+  MigrationManager,
+  VersionedObject,
+} from './lib/migration-manager';
 export { Persistence } from './lib/persistence';
 export { roundToMultipleOf } from './lib/round-to-multiple-of';
 export { toCsv } from './lib/to-csv';