feat: add AgrarmonitorBetriebId to Client entity

paperless-backend/src/database/entities/client.entity.ts

@@ -10,4 +10,7 @@ export class Client {
 
   @Column({ type: 'int' })
   PaperlessUserId!: number;
+
+  @Column({ type: 'int', nullable: true })
+  AgrarmonitorBetriebId!: number | null;
 }