Enable DependaBot & CodeQL

Author: jwinskye

.github/dependabot.yml

@@ -0,0 +1,7 @@
+version: 2
+updates:
+  - package-ecosystem: "nuget"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 10

.github/workflows/codeql.yml

@@ -0,0 +1,33 @@
+name: CodeQL
+on:
+  push: { branches: [ "main" ] }
+  pull_request: { branches: [ "main" ] }
+  schedule:
+    - cron: "0 3 * * 1"  # weekly
+
+jobs:
+  analyze:
+    permissions:
+      contents: read
+      security-events: write
+      actions: read
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ "csharp" ]
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: ${{ matrix.language }}
+
+      - name: Autobuild
+        uses: github/codeql-action/autobuild@v3
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v3