ci: add CodeQL, Semgrep, Gitleaks, Trivy security scanning

.github/workflows/codeql.yml

@@ -0,0 +1,42 @@
+name: "CodeQL Security Analysis"
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+  schedule:
+    # Run weekly on Monday at 6 AM UTC
+    - cron: '0 6 * * 1'
+
+jobs:
+  analyze:
+    name: Analyze Code
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: ['javascript']
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: ${{ matrix.language }}
+          queries: security-extended # More thorough than default
+
+      - name: Autobuild
+        uses: github/codeql-action/autobuild@v3
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v3
+        with:
+          category: "/language:${{matrix.language}}"