chore: Add dependabot and CodeQL security scanning

Author: rz1989s

.github/dependabot.yml

@@ -0,0 +1,27 @@
+version: 2
+updates:
+  # Gradle dependencies
+  - package-ecosystem: "gradle"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "monday"
+    open-pull-requests-limit: 5
+    labels:
+      - "dependencies"
+      - "gradle"
+    commit-message:
+      prefix: "chore(deps)"
+
+  # GitHub Actions
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "monday"
+    open-pull-requests-limit: 3
+    labels:
+      - "dependencies"
+      - "ci"
+    commit-message:
+      prefix: "chore(ci)"

.github/workflows/codeql.yml

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+name: CodeQL Security Analysis
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+  schedule:
+    - cron: '0 0 * * 1'
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up JDK
+        uses: actions/setup-java@v4
+        with:
+          java-version: '17'
+          distribution: 'temurin'
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: java-kotlin
+          queries: security-extended
+
+      - name: Build with Gradle
+        run: ./gradlew build -x test
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v3
+        with:
+          category: "/language:java-kotlin"