refactor(frontend): lint, one session guard, one request helper, one user context

eslint.config.js

@@ -0,0 +1,28 @@
+import js from '@eslint/js';
+import globals from 'globals';
+import reactHooks from 'eslint-plugin-react-hooks';
+
+export default [
+    {ignores: ['dist']},
+    js.configs.recommended,
+    {
+        files: ['**/*.{js,jsx}'],
+        languageOptions: {
+            parserOptions: {ecmaFeatures: {jsx: true}},
+            globals: {
+                ...globals.browser,
+                // set by `define` in vite.config.js
+                __TRANSLATIONS_VERSION__: 'readonly',
+                __BUILD_COMMIT__: 'readonly',
+                __BUILD_TIME__: 'readonly',
+            },
+        },
+        plugins: {'react-hooks': reactHooks},
+        // Only the two classic rules: the React Compiler rules of the plugin's recommended set are a later step.
+        rules: {
+            'react-hooks/rules-of-hooks': 'error',
+            'react-hooks/exhaustive-deps': 'error',
+        },
+    },
+    {files: ['*.config.js'], languageOptions: {globals: globals.node}},
+];