feat: 관리자 회원 관리 API (/api/admin/members)

목록/역할 변경/상태 변경/삭제. 본인 계정 변경·삭제 차단.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/main/java/com/sb/web/auth/dto/MemberAdminResponse.java

@@ -0,0 +1,37 @@
+package com.sb.web.auth.dto;
+
+import com.sb.web.auth.domain.Member;
+import lombok.Builder;
+import lombok.Data;
+
+import java.time.LocalDateTime;
+
+/**
+ * 관리자용 회원 정보 응답 (비밀번호 제외).
+ */
+@Data
+@Builder
+public class MemberAdminResponse {
+
+    private Long id;
+    private String loginId;
+    private String name;
+    private String email;
+    private String role;     // USER / ADMIN
+    private String status;   // ACTIVE / SUSPENDED / WITHDRAWN
+    private String provider; // LOCAL / 소셜
+    private LocalDateTime createdAt;
+
+    public static MemberAdminResponse from(Member m) {
+        return MemberAdminResponse.builder()
+                .id(m.getId())
+                .loginId(m.getLoginId())
+                .name(m.getName())
+                .email(m.getEmail())
+                .role(m.getRole())
+                .status(m.getStatus())
+                .provider(m.getProvider())
+                .createdAt(m.getCreatedAt())
+                .build();
+    }
+}