[FEATURE] 초기 아바타 설정

src/main/java/com/todaysgym/todaysgym/avatar/Avatar.java

@@ -38,6 +38,11 @@ private static Avatar getMaxAvatarLevel() {
             .max(Comparator.comparingInt(Avatar::getLevel)).get();
     }
 
+    public static Avatar getInitialAvatar() {
+        return Arrays.stream(values())
+            .min(Comparator.comparingInt(Avatar::getLevel)).get();
+    }
+
     public String getImgUrl() {
         return imgUrl;
     }

src/main/java/com/todaysgym/todaysgym/member/MemberService.java

@@ -156,4 +156,14 @@ public boolean checkAndMyAvatarLevelUp(Long memberId) {
     public void memberLevelUp(Member member, Avatar avatar) {
         member.changeAvatar(avatar);
     }
+
+    @Transactional
+    public void setInitialAvatar(Member member) {
+        Avatar initialMyAvatar = getInitialAvatar();
+        memberLevelUp(member, initialMyAvatar);
+    }
+
+    private Avatar getInitialAvatar() {
+        return Avatar.getInitialAvatar();
+    }
 }