chore: upgrade eslint to v9 to fix security vulnerability

- Updates eslint to v9.20.0 to resolve Dependabot alert #50
- Migrates config to flat format (eslint.config.js)
- Updates typescript-eslint and eslint-plugin-solid
- Fixes lint error in UnifiedBackups.tsx

frontend-modern/.eslintignore

@@ -1,3 +0,0 @@
-dist
-node_modules
-public

frontend-modern/.eslintrc.cjs

@@ -1,41 +0,0 @@
-module.exports = {
-  root: true,
-  env: {
-    browser: true,
-    es2021: true,
-    node: true,
-  },
-  extends: [
-    'eslint:recommended',
-    'plugin:@typescript-eslint/recommended',
-    'plugin:solid/typescript',
-    'prettier',
-  ],
-  parser: '@typescript-eslint/parser',
-  parserOptions: {
-    ecmaVersion: 'latest',
-    sourceType: 'module',
-  },
-  plugins: ['@typescript-eslint', 'solid'],
-  ignorePatterns: ['dist', 'node_modules'],
-  rules: {
-    '@typescript-eslint/no-unused-vars': [
-      'warn',
-      {
-        argsIgnorePattern: '^_',
-        varsIgnorePattern: '^_',
-        caughtErrorsIgnorePattern: '^_',
-      },
-    ],
-    '@typescript-eslint/no-unused-expressions': 'off',
-    '@typescript-eslint/no-explicit-any': 'off',
-    'no-case-declarations': 'off',
-    'no-useless-escape': 'off',
-    'prefer-const': 'off',
-    'solid/reactivity': 'off',
-    'solid/prefer-for': 'off',
-    'solid/style-prop': 'off',
-    'solid/components-return-once': 'off',
-    'solid/self-closing-comp': 'off',
-  },
-};

frontend-modern/eslint.config.js

@@ -0,0 +1,45 @@
+import js from "@eslint/js";
+import tseslint from "typescript-eslint";
+import solid from "eslint-plugin-solid";
+import prettier from "eslint-config-prettier";
+import globals from "globals";
+
+export default tseslint.config(
+    { ignores: ["dist", "public", "node_modules"] },
+    js.configs.recommended,
+    ...tseslint.configs.recommended,
+    {
+        files: ["**/*.{ts,tsx}"],
+        languageOptions: {
+            globals: { ...globals.browser, ...globals.node },
+            parserOptions: {
+                sourceType: "module",
+            },
+        },
+        plugins: {
+            solid,
+        },
+        rules: {
+            ...solid.configs.typescript.rules,
+            "@typescript-eslint/no-unused-vars": [
+                "warn",
+                {
+                    argsIgnorePattern: "^_",
+                    varsIgnorePattern: "^_",
+                    caughtErrorsIgnorePattern: "^_",
+                },
+            ],
+            "@typescript-eslint/no-unused-expressions": "off",
+            "@typescript-eslint/no-explicit-any": "off",
+            "no-case-declarations": "off",
+            "no-useless-escape": "off",
+            "prefer-const": "off",
+            "solid/reactivity": "off",
+            "solid/prefer-for": "off",
+            "solid/style-prop": "off",
+            "solid/components-return-once": "off",
+            "solid/self-closing-comp": "off",
+        },
+    },
+    prettier
+);

frontend-modern/package.json

@@ -39,22 +39,25 @@
     "seroval-plugins": "^1.4.1"
   },
   "devDependencies": {
+    "@eslint/js": "^9.39.2",
     "@solidjs/testing-library": "^0.8.5",
     "@tailwindcss/typography": "^0.5.19",
     "@testing-library/jest-dom": "^6.5.0",
     "@types/node": "^20.10.0",
-    "@typescript-eslint/eslint-plugin": "^8.0.0",
-    "@typescript-eslint/parser": "^8.0.0",
+    "@typescript-eslint/eslint-plugin": "^8.24.0",
+    "@typescript-eslint/parser": "^8.24.0",
     "@vitest/coverage-v8": "^3.2.4",
     "autoprefixer": "^10.4.0",
-    "eslint": "^8.57.0",
-    "eslint-config-prettier": "^9.0.0",
-    "eslint-plugin-solid": "^0.14.0",
+    "eslint": "^9.20.0",
+    "eslint-config-prettier": "^10.0.0",
+    "eslint-plugin-solid": "^0.14.5",
+    "globals": "^17.3.0",
     "jsdom": "^24.1.0",
     "postcss": "^8.4.0",
     "prettier": "^3.3.0",
     "tailwindcss": "^3.4.18",
     "typescript": "^5.3.0",
+    "typescript-eslint": "^8.54.0",
     "vite": "^6.4.1",
     "vite-plugin-solid": "^2.8.0",
     "vitest": "^3.2.4"

frontend-modern/src/components/Backups/UnifiedBackups.tsx

@@ -1256,7 +1256,12 @@ const UnifiedBackups: Component = () => {
       </Show>
 
       {/* Removed old PBS table */}
-      <Show when={false && sortedPBSInstances().length > 0}>
+      <Show
+        when={
+          // eslint-disable-next-line no-constant-binary-expression
+          false && sortedPBSInstances().length > 0
+        }
+      >
         <Card padding="none" class="overflow-hidden">
           <div class="overflow-x-auto" style="scrollbar-width: none; -ms-overflow-style: none;">
             <style>{`