build: update npm install command to use --legacy-peer-deps

This change modifies the build scripts to use --legacy-peer-deps flag when installing npm dependencies to resolve potential peer dependency conflicts during the build process. The change is applied to both bash (build.sh) and batch (build.bat) build scripts.

frontend/node_modules/espree/lib/options.js

@@ -19,9 +19,7 @@ const SUPPORTED_VERSIONS = [
     12, // 2021
     13, // 2022
     14, // 2023
-    15, // 2024
-    16, // 2025
-    17 // 2026
+    15 // 2024
 ];
 
 /**
@@ -29,7 +27,7 @@ const SUPPORTED_VERSIONS = [
  * @returns {number} The latest ECMAScript version.
  */
 export function getLatestEcmaVersion() {
-    return SUPPORTED_VERSIONS.at(-1);
+    return SUPPORTED_VERSIONS[SUPPORTED_VERSIONS.length - 1];
 }
 
 /**

frontend/node_modules/espree/lib/token-translator.js

@@ -40,7 +40,7 @@ const Token = {
  */
 function convertTemplatePart(tokens, code) {
     const firstToken = tokens[0],
-        lastTemplateToken = tokens.at(-1);
+        lastTemplateToken = tokens[tokens.length - 1];
 
     const token = {
         type: Token.Template,

frontend/node_modules/espree/lib/version.js

@@ -1,3 +1,3 @@
-const version = "10.4.0";
+const version = "9.6.1";
 
 export default version;