Configure GitHub's CodeQL feature

.github/codeql/codeql-config.yml

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+name: "Quintolin CodeQL config"
+queries:
+  - uses: security-extended
+  - uses: security-and-quality
+paths-ignore:
+  - doc
+  - legacy

.github/workflows/codeql.yml

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+name: "CodeQL"
+
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: '42 7 * * 2' # value suggested by GitHub UI
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+    timeout-minutes: 360
+    permissions:
+      security-events: write
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'javascript-typescript' ]
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: ${{ matrix.language }}
+          config-file: ./.github/codeql/codeql-config.yml
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v3
+        with:
+          category: "/language:${{matrix.language}}"