Add linting and format checks (#20)

* Add VS Code, markdownlint, and prettier configs
* Format and lint all files
* Add ESLint and MDX plugin
* Add GitHub Actions
* Add pre-commit hooks and update markdownlint step

Author: danbarr

.github/actions/setup/action.yaml

@@ -0,0 +1,24 @@
+name: 'Setup Action'
+description: 'Checks out the repo, sets up node, and installs dependencies'
+runs:
+  using: 'composite'
+  steps:
+    - name: Checkout repository
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+
+    - name: Set up Node.js
+      uses: actions/setup-node@39370e3970a6d050c480ffad4ff0ed4d3fdee5af # v4
+      with:
+        node-version: '22'
+
+    - name: Cache dependencies
+      id: cache
+      uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4.2.0
+      with:
+        path: ./node_modules
+        key: modules-${{ hashFiles('package-lock.json') }}
+
+    - name: Install dependencies
+      if: steps.cache.outputs.cache-hit != 'true'
+      run: npm ci
+      shell: bash

.github/dependabot.yaml

@@ -0,0 +1,20 @@
+version: 2
+updates:
+  - package-ecosystem: 'npm'
+    directory: '/'
+    schedule:
+      interval: 'daily'
+    groups:
+      docusaurus:
+        patterns:
+          - '*docusaurus*'
+    ignore:
+      # Pin key docusaurus dependencies to major versions
+      - dependency-name: '@mdx-js/react'
+        update-types: ['version-update:semver-major']
+      - dependency-name: 'prism-react-renderer'
+        update-types: ['version-update:semver-major']
+  - package-ecosystem: 'github-actions'
+    directory: '/'
+    schedule:
+      interval: 'daily'

.github/dependabot.yml

@@ -0,0 +1,37 @@
+name: Static checks
+
+on:
+  workflow_call:
+
+jobs:
+  lint:
+    name: Lint and format checks
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+
+      - name: Setup
+        uses: ./.github/actions/setup
+
+      - name: Run ESLint
+        run: npm run eslint
+
+      - name: Run markdownlint
+        run: npm run markdownlint
+
+      - name: Run Prettier
+        run: npm run prettier
+
+  build:
+    name: Build site
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+
+      - name: Setup
+        uses: ./.github/actions/setup
+
+      - name: Build site
+        run: npm run build

.github/workflows/_static-checks.yaml

@@ -0,0 +1,13 @@
+name: On PR
+
+on:
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  static-checks:
+    name: Static checks
+    uses: ./.github/workflows/_static-checks.yaml
+    secrets: inherit

.github/workflows/on-pr.yaml

@@ -0,0 +1 @@
+npx lint-staged

.husky/pre-commit

@@ -0,0 +1,5 @@
+{
+  "*.{js,jsx,ts,tsx,mjs,cjs}": ["npx prettier --write", "npx eslint --fix"],
+  "*.md": ["npx prettier --write", "npx markdownlint-cli2 --fix"],
+  "*.css": ["npx prettier --write"]
+}

.lintstagedrc

@@ -0,0 +1,35 @@
+{
+  "heading-style": {
+    "style": "atx"
+  },
+  "ul-style": {
+    "style": "dash"
+  },
+  "line-length": {
+    "line_length": 80,
+    "code_blocks": false,
+    "tables": false
+  },
+  "hr-style": {
+    "style": "---"
+  },
+  "proper-names": {
+    "names": ["CodeGate", "Copilot", "GitHub"],
+    "code_blocks": false
+  },
+  "code-block-style": {
+    "style": "fenced"
+  },
+  "code-fence-style": {
+    "style": "backtick"
+  },
+  "emphasis-style": {
+    "style": "underscore"
+  },
+  "strong-style": {
+    "style": "asterisk"
+  },
+  "table-pipe-style": {
+    "style": "leading_and_trailing"
+  }
+}

.markdownlint.json

@@ -0,0 +1,9 @@
+{
+  "jsxSingleQuote": true,
+  "printWidth": 80,
+  "proseWrap": "always",
+  "singleQuote": true,
+  "tabWidth": 2,
+  "trailingComma": "es5",
+  "useTabs": false
+}