feat(oauth): OAuth 제공자 목록에 카카오 추가, 로직 개선

Author: m-a-king

src/main/java/com/somemore/global/auth/oauth/domain/OAuthProvider.java

@@ -4,7 +4,9 @@
 
 @Getter
 public enum OAuthProvider {
-    NAVER("naver");
+    NAVER("naver"),
+    KAKAO("kakao"),
+    ;
 
     private final String providerName;
 
@@ -14,7 +16,7 @@ public enum OAuthProvider {
 
     public static OAuthProvider from(String providerName) {
         for (OAuthProvider provider : values()) {
-            if (provider.providerName.equals(providerName)) {
+            if (provider.providerName.equalsIgnoreCase(providerName)) {
                 return provider;
             }
         }