Fix TypeScript error in tests

The `backupProxySuccess` property was being assigned to the `debugInfo` object in the `testSupabaseConnection` function, but it was not defined in the type definition. This commit adds the `backupProxySuccess` property to the type definition of the `debugInfo` object to resolve the TypeScript error.

src/lib/supabase/tests.ts

@@ -47,7 +47,8 @@ export const testSupabaseConnection = async () => {
       usingProxy,
       keyLength: supabaseKey.length,
       browserInfo: navigator.userAgent,
-      timestamp: new Date().toISOString()
+      timestamp: new Date().toISOString(),
+      backupProxySuccess: false  // 타입 오류 수정: backupProxySuccess 속성 추가
     }
   };