Fix login 401, admin permission, video links serialization, and admin UI styling

- Fix UserInfo boolean field naming (isAdmin → admin) for proper Jackson/MyBatis mapping
- Configure Google OAuth audience with actual client ID to fix token verification
- Parse CLOB fields and convert Oracle TIMESTAMP in restaurant video links API
- Add explicit bg-white/text-gray-900 to admin page inputs, selects, and table headers
- Add keyPrefix to RestaurantList to avoid duplicate React keys across desktop/mobile

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend-java/src/main/java/com/tasteby/domain/UserInfo.java

@@ -16,7 +16,7 @@ public class UserInfo {
     private String nickname;
     private String avatarUrl;
     @JsonProperty("is_admin")
-    private boolean isAdmin;
+    private boolean admin;
     private String provider;
     private String providerId;
     private String createdAt;

backend-java/src/main/java/com/tasteby/service/AuthService.java

@@ -6,6 +6,7 @@ import com.google.api.client.http.javanet.NetHttpTransport;
 import com.google.api.client.json.gson.GsonFactory;
 import com.tasteby.domain.UserInfo;
 import com.tasteby.security.JwtTokenProvider;
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.http.HttpStatus;
 import org.springframework.stereotype.Service;
 import org.springframework.web.server.ResponseStatusException;
@@ -20,12 +21,13 @@ public class AuthService {
     private final JwtTokenProvider jwtProvider;
     private final GoogleIdTokenVerifier verifier;
 
-    public AuthService(UserService userService, JwtTokenProvider jwtProvider) {
+    public AuthService(UserService userService, JwtTokenProvider jwtProvider,
+                       @Value("${app.google.client-id}") String googleClientId) {
         this.userService = userService;
         this.jwtProvider = jwtProvider;
         this.verifier = new GoogleIdTokenVerifier.Builder(
                 new NetHttpTransport(), GsonFactory.getDefaultInstance())
-                .setAudience(Collections.emptyList()) // Accept any audience
+                .setAudience(Collections.singletonList(googleClientId))
                 .build();
     }
 

backend-java/src/main/java/com/tasteby/service/RestaurantService.java

@@ -35,7 +35,13 @@ public class RestaurantService {
 
     public List<Map<String, Object>> findVideoLinks(String restaurantId) {
         var rows = mapper.findVideoLinks(restaurantId);
-        return rows.stream().map(JsonUtil::lowerKeys).toList();
+        return rows.stream().map(row -> {
+            var m = JsonUtil.lowerKeys(row);
+            m.put("foods_mentioned", JsonUtil.parseStringList(m.get("foods_mentioned")));
+            m.put("evaluation", JsonUtil.parseMap(m.get("evaluation")));
+            m.put("guests", JsonUtil.parseStringList(m.get("guests")));
+            return m;
+        }).toList();
     }
 
     public void update(String id, Map<String, Object> fields) {