ci: add JDK 26 to build matrix

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: dfa1

.github/workflows/ci.yml

@@ -10,14 +10,18 @@ jobs:
   build:
     runs-on: ubuntu-latest
 
+    strategy:
+      matrix:
+        java-version: [ '25', '26' ]
+
     steps:
       - uses: actions/checkout@v4
 
-      - name: Set up Azul Zulu JDK 25
+      - name: Set up Azul Zulu JDK ${{ matrix.java-version }}
         uses: actions/setup-java@v4
         with:
           distribution: zulu
-          java-version: '25'
+          java-version: ${{ matrix.java-version }}
 
       - name: Cache Maven repository
         uses: actions/cache@v4