fine-tune native image config

backend/pom.xml

@@ -157,10 +157,10 @@
       <plugin>
         <groupId>com.google.cloud.tools</groupId>
         <artifactId>jib-maven-plugin</artifactId>
-        <version>3.4.5</version>
+        <version>3.5.1</version>
         <configuration>
           <from>
-            <!-- distroless glibc base — matches GraalVM native binary ABI on Linux x86_64 -->
+            <!-- distroless glibc base — multi-arch (amd64 + arm64), matches GraalVM native binary ABI -->
             <image>gcr.io/distroless/base-nossl-debian12</image>
           </from>
           <to>
@@ -177,6 +177,10 @@
               <implementation>
                 com.google.cloud.tools.jib.maven.extension.nativeimage.JibNativeImageExtension
               </implementation>
+              <properties>
+                <!-- Must match <imageName> in native-maven-plugin -->
+                <imageName>ai-teacher-backend</imageName>
+              </properties>
             </pluginExtension>
           </pluginExtensions>
         </configuration>
@@ -228,6 +232,8 @@
                 <buildArg>-H:-EnableLoggingFeature</buildArg>
                 <buildArg>-R:MaxHeapSize=128m</buildArg>
                 <buildArg>-R:MinHeapSize=32m</buildArg>
+                <!-- Limit native-image compiler RAM (build time, not runtime) -->
+                <buildArg>-J-Xmx8g</buildArg>
               </buildArgs>
             </configuration>
           </plugin>