fix: derive JAVA_HOME from jar binary and add to PATH

java binary may not be on PATH directly in the build container.
Derive JAVA_HOME from the jar binary location (which we know works)
and prepend JAVA_HOME/bin to PATH so sonar-scanner can find java.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitea/workflows/sonarqube.yml

@@ -72,10 +72,14 @@ jobs:
 
       - name: SonarQube Analysis
         run: |
-          # Derive JAVA_HOME from the java binary on PATH (set by build image)
+          # Derive JAVA_HOME from jar binary (java may not be on PATH directly)
           if [ -z "$JAVA_HOME" ]; then
-            export JAVA_HOME=$(dirname $(dirname $(readlink -f $(which java))))
+            JAR_PATH=$(readlink -f $(which jar) 2>/dev/null || find / -name jar -type f 2>/dev/null | head -1)
+            export JAVA_HOME=$(dirname $(dirname "$JAR_PATH"))
           fi
+          export PATH="$JAVA_HOME/bin:$PATH"
+          echo "JAVA_HOME=$JAVA_HOME"
+          java -version
           sonar-scanner \
             -Dsonar.host.url="$SONAR_HOST_URL" \
             -Dsonar.token="$SONAR_TOKEN" \