feat(server): conditionally run facial recognition nightly (#11080)

* only run nightly if new person

* add tests

* use string instead of date

* update sql

* update tests

* simplify condition

server/src/interfaces/person.interface.ts

@@ -64,4 +64,5 @@ export interface IPersonRepository {
   getNumberOfPeople(userId: string): Promise<PeopleStatistics>;
   reassignFaces(data: UpdateFacesData): Promise<number>;
   update(entity: Partial<PersonEntity>): Promise<PersonEntity>;
+  getLatestFaceDate(): Promise<string | undefined>;
 }