feat(markers): implement marker entity & service

src/main/java/com/ddf/vodsystem/repositories/MarkerRepository.java

@@ -0,0 +1,15 @@
+package com.ddf.vodsystem.repositories;
+
+import com.ddf.vodsystem.entities.Marker;
+import com.ddf.vodsystem.entities.User;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.stereotype.Repository;
+
+import java.util.List;
+
+@Repository
+public interface MarkerRepository extends JpaRepository<Marker, Long> {
+    @Query("SELECT m FROM Marker m WHERE m.user = ?1")
+    List<Marker> findByUser(User user);
+}