Add code quality workflows

.eslintrc.json

@@ -1,3 +1,3 @@
 {
-  "extends": "next/core-web-vitals"
+  "extends": ["next/core-web-vitals", "next/typescript", "prettier"]
 }

.github/workflows/ci.yml

@@ -0,0 +1,35 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+permissions:
+  contents: read
+
+jobs:
+  qa:
+    name: Run QA tools
+    runs-on: ubuntu-24.04
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - uses: actions/setup-node@v6
+        with:
+          node-version: 'lts/*'
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run ESLint
+        run: npm run lint
+
+      - name: Run format check
+        run: npm run format:check

.github/workflows/codeql.yml

@@ -0,0 +1,48 @@
+name: CodeQL analysis
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+  schedule:
+    - cron: '0 8 * * *' # every day at 8 AM UTC
+
+jobs:
+  analyze:
+    name: Analyze code
+    runs-on: ubuntu-24.04
+    permissions:
+      # required for all workflows
+      security-events: write
+      # required to fetch internal or private CodeQL packs
+      packages: read
+      # only required for workflows in private repositories
+      actions: read
+      # repository contents
+      contents: read
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - language: javascript-typescript
+            build-mode: none
+          - language: actions
+            build-mode: none
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v4
+        with:
+          languages: ${{ matrix.language }}
+          build-mode: none
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v4
+        with:
+          category: '/language:${{matrix.language}}'

.github/workflows/dependency-scan.yml

@@ -0,0 +1,19 @@
+name: Dependency scan
+
+on:
+  pull_request:
+    branches:
+      - main
+
+permissions:
+  contents: read
+
+jobs:
+  dependency-review:
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Dependency Review
+        uses: actions/dependency-review-action@v4

.prettierrc

@@ -0,0 +1,6 @@
+{
+  "singleQuote": true,
+  "trailingComma": "all",
+  "printWidth": 120,
+  "plugins": ["prettier-plugin-tailwindcss"]
+}

eslint.config.mjs

@@ -0,0 +1,25 @@
+import nextVitals from 'eslint-config-next/core-web-vitals';
+import nextTs from 'eslint-config-next/typescript';
+import prettier from 'eslint-config-prettier/flat';
+import { defineConfig, globalIgnores } from 'eslint/config';
+
+const eslintConfig = defineConfig([
+  ...nextVitals,
+  ...nextTs,
+  prettier,
+  // Override default ignores of eslint-config-next.
+  globalIgnores([
+    // Default ignores of eslint-config-next:
+    '.next/**',
+    'out/**',
+    'build/**',
+    'next-env.d.ts',
+  ]),
+  {
+    rules: {
+      'react-hooks/set-state-in-effect': 'off',
+    },
+  },
+]);
+
+export default eslintConfig;

next.config.js

@@ -1,4 +1,4 @@
 /** @type {import('next').NextConfig} */
-const nextConfig = {}
+const nextConfig = {};
 
-module.exports = nextConfig
+module.exports = nextConfig;