fix(ci): add custom CodeQL workflow for Python-only analysis

.github/workflows/codeql.yml

@@ -0,0 +1,40 @@
+# SPDX-FileCopyrightText: 2026 bartzbeielstein
+#
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+name: CodeQL
+
+on:
+  push:
+    branches: [main, develop]
+  pull_request:
+    branches: [main]
+  schedule:
+    - cron: "30 1 * * 1"  # Weekly on Monday
+
+jobs:
+  analyze:
+    name: Analyze (python)
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: python
+          queries: security-extended
+
+      - name: Autobuild
+        uses: github/codeql-action/autobuild@v3
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v3
+        with:
+          category: /language:python