Refactor password reset logic and update UI components for better user experience

- Removed the minimum password length validation from the backend, simplifying the password reset process.
- Updated the password encryption method to utilize `EncryptUtil`, enhancing security and maintainability.
- Adjusted the `UserPasswordResetModal` component to reset alert states upon closing, improving user feedback.
- Modified the z-index values in the `Popover` and `Select` components for better layering and visibility in the UI.

These changes streamline the password reset functionality and enhance the overall user interface, ensuring a more intuitive experience for administrators.

backend-node/src/controllers/adminController.ts

@@ -3728,17 +3728,6 @@ export const resetUserPassword = async (
     return;
   }
 
-  // 비밀번호 길이 검증 (최소 4자)
-  if (newPassword.length < 4) {
-    res.status(400).json({
-      success: false,
-      result: false,
-      message: "비밀번호는 최소 4자 이상이어야 합니다.",
-      msg: "비밀번호는 최소 4자 이상이어야 합니다.",
-    });
-    return;
-  }
-
   try {
     // 1. Raw Query로 사용자 존재 여부 확인
     const currentUser = await queryOne<any>(
@@ -3756,19 +3745,10 @@ export const resetUserPassword = async (
       return;
     }
 
-    // 2. 비밀번호 암호화 (기존 Java 로직과 동일)
+    // 2. 비밀번호 암호화 (EncryptUtil 사용)
     let encryptedPassword: string;
     try {
-      // EncryptUtil과 동일한 암호화 사용
-      const crypto = require("crypto");
-      const keyName = "ILJIAESSECRETKEY";
-      const algorithm = "aes-128-ecb";
-
-      // AES-128-ECB 암호화
-      const cipher = crypto.createCipher(algorithm, keyName);
-      let encrypted = cipher.update(newPassword, "utf8", "hex");
-      encrypted += cipher.final("hex");
-      encryptedPassword = encrypted.toUpperCase();
+      encryptedPassword = EncryptUtil.encrypt(newPassword);
     } catch (encryptError) {
       logger.error("비밀번호 암호화 중 오류 발생", {
         error: encryptError,