Update CodeQL workflow for Java 21 analysis

.github/dependabot.yml

@@ -0,0 +1,55 @@
+version: 2
+
+updates:
+  # Maven / Spring Boot dependencies
+  - package-ecosystem: "maven"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "sunday"
+      time: "09:00"
+    open-pull-requests-limit: 10
+    rebase-strategy: "auto"
+
+    # Group updates to reduce noise in dev
+    groups:
+      spring:
+        patterns:
+          - "org.springframework*"
+          - "org.springframework.boot*"
+      testing:
+        patterns:
+          - "org.junit*"
+          - "org.mockito*"
+          - "org.assertj*"
+          - "org.testcontainers*"
+      build-plugins:
+        patterns:
+          - "org.apache.maven.plugins*"
+          - "io.spring.javaformat*"
+          - "com.diffplug.spotless*"
+          - "org.sonarsource.scanner.maven*"
+      misc:
+        patterns:
+          - "*"
+
+    # Avoid risky breaking changes automatically (you upgrade these intentionally)
+    ignore:
+      - dependency-name: "org.springframework.boot"
+        update-types: ["version-update:semver-major"]
+      - dependency-name: "org.springframework"
+        update-types: ["version-update:semver-major"]
+      - dependency-name: "org.springframework.security"
+        update-types: ["version-update:semver-major"]
+      - dependency-name: "org.hibernate.orm"
+        update-types: ["version-update:semver-major"]
+
+  # GitHub Actions used in workflows
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "sunday"
+      time: "09:00"
+    open-pull-requests-limit: 5
+    rebase-strategy: "auto"

.github/workflows/codeql.yml

@@ -0,0 +1,57 @@
+name: "CodeQL"
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+  schedule:
+    - cron: "33 19 * * 4"
+
+jobs:
+  analyze:
+    name: Analyze (Java 21)
+    runs-on: ubuntu-latest
+
+    permissions:
+      security-events: write
+      actions: read
+      contents: read
+      packages: read
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up JDK 21
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: "21"
+          cache: maven
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v4
+        with:
+          languages: java-kotlin
+          build-mode: manual
+          queries: security-extended,security-and-quality
+
+      # Maven (Spring Initializr usually uses Maven)
+      - name: Build with Maven
+        if: hashFiles('pom.xml') != ''
+        run: |
+          chmod +x mvnw || true
+          ./mvnw -B -DskipTests clean package || mvn -B -DskipTests clean package
+
+      # Gradle (only runs if Gradle files exist)
+      - name: Build with Gradle
+        if: hashFiles('build.gradle', 'build.gradle.kts') != ''
+        run: |
+          chmod +x gradlew || true
+          ./gradlew build -x test
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v4
+        with:
+          category: "/language:java-kotlin"