Enable ESLint no-undef rule

frontend/eslint.config.mjs

@@ -1,6 +1,7 @@
 // @ts-check
 
 import eslint from '@eslint/js';
+import globals from "globals";
 import { defineConfig } from 'eslint/config';
 import tseslint from 'typescript-eslint';
 
@@ -17,7 +18,6 @@ export default defineConfig(
     "rules": {
       "no-empty": "off", // Temporarily disabled until codebase conformant
       "no-empty-pattern": "off", // Temporarily disabled until codebase conformant
-      "no-undef": "off", // Temporarily disabled until codebase conformant
       "no-useless-escape": "off", // Temporarily disabled until codebase conformant
       "no-case-declarations": "off", // Temporarily disabled until codebase conformant
       "prefer-const": "off", // Temporarily disabled until codebase conformant
@@ -28,5 +28,29 @@ export default defineConfig(
       "@typescript-eslint/no-unused-expressions": "off", // Temporarily disabled until codebase conformant
       "@typescript-eslint/no-unused-vars": "off", // Temporarily disabled until codebase conformant
     },
+  },
+  // Config for browser scripts
+  {
+    files: [
+      "src",
+    ],
+    languageOptions: {
+      globals: {
+        ...globals.browser,
       }
+    }
+  },
+  // Config for node scripts
+  {
+    files: [
+      "scripts/*.js",
+      "postcss.config.js",
+      "tailwind.config.js",
+    ],
+    languageOptions: {
+      globals: {
+        ...globals.node,
+      }
+    }
+  },
 );

frontend/package-lock.json

@@ -26,6 +26,7 @@
         "@testing-library/user-event": "^13.5.0",
         "autoprefixer": "^10.4.21",
         "axios": "^1.9.0",
+        "globals": "^16.3.0",
         "i18next": "^25.2.1",
         "i18next-browser-languagedetector": "^8.1.0",
         "i18next-http-backend": "^3.0.2",
@@ -447,6 +448,15 @@
         "node": ">=6.9.0"
       }
     },
+    "node_modules/@babel/traverse/node_modules/globals": {
+      "version": "11.12.0",
+      "resolved": "https://registry.npmjs.org/globals/-/globals-11.12.0.tgz",
+      "integrity": "sha512-WOBp/EEGUiIsJSp7wcv/y6MO+lV9UoncWqxuFfm8eBwzWNgyfBd6Gz+IeKQ9jCmyhoH99g15M3T+QaVHFjizVA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=4"
+      }
+    },
     "node_modules/@babel/types": {
       "version": "7.28.2",
       "resolved": "https://registry.npmjs.org/@babel/types/-/types-7.28.2.tgz",
@@ -5595,12 +5605,15 @@
       }
     },
     "node_modules/globals": {
-      "version": "11.12.0",
+      "version": "16.3.0",
-      "resolved": "https://registry.npmjs.org/globals/-/globals-11.12.0.tgz",
+      "resolved": "https://registry.npmjs.org/globals/-/globals-16.3.0.tgz",
-      "integrity": "sha512-WOBp/EEGUiIsJSp7wcv/y6MO+lV9UoncWqxuFfm8eBwzWNgyfBd6Gz+IeKQ9jCmyhoH99g15M3T+QaVHFjizVA==",
+      "integrity": "sha512-bqWEnJ1Nt3neqx2q5SFfGS8r/ahumIakg3HcwtNlrVlwXIeNumWn/c7Pn/wKzGhf6SaW6H6uWXLqC30STCMchQ==",
       "license": "MIT",
       "engines": {
-        "node": ">=4"
+        "node": ">=18"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/sindresorhus"
       }
     },
     "node_modules/gonzales-pe": {

frontend/package.json

@@ -22,6 +22,7 @@
     "@testing-library/user-event": "^13.5.0",
     "autoprefixer": "^10.4.21",
     "axios": "^1.9.0",
+    "globals": "^16.3.0",
     "i18next": "^25.2.1",
     "i18next-browser-languagedetector": "^8.1.0",
     "i18next-http-backend": "^3.0.2",