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/eslint/messages/file-not-found.js

@@ -1,9 +1,9 @@
 "use strict";
 
-module.exports = function (it) {
-	const { pattern, globDisabled } = it;
+module.exports = function(it) {
+    const { pattern, globDisabled } = it;
 
-	return `
+    return `
 No files matching the pattern "${pattern}"${globDisabled ? " (with disabling globs)" : ""} were found.
 Please check for typing mistakes in the pattern.
 `.trimStart();