feature: 미션 엔티티 구현

src/main/java/com/depromeet/stonebed/domain/mission/dao/MissionRepository.java

@@ -0,0 +1,6 @@
+package com.depromeet.stonebed.domain.mission.dao;
+
+import com.depromeet.stonebed.domain.mission.domain.Mission;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface MissionRepository extends JpaRepository<Mission, Long> {}

src/main/java/com/depromeet/stonebed/domain/mission/domain/Mission.java

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+package com.depromeet.stonebed.domain.mission.domain;
+
+import com.depromeet.stonebed.domain.common.BaseTimeEntity;
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.Size;
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@Entity
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class Mission extends BaseTimeEntity {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "mission_id")
+    private Long id;
+
+    @NotBlank
+    @Size(max = 100)
+    @Column(name = "title", nullable = false, length = 100)
+    private String title;
+
+    @Builder
+    public Mission(String title) {
+        this.title = title;
+    }
+}