fix: AIUI copy uses rsync to handle same-file in CI workspace

The CI build server's /opt/archipelago/web-ui/aiui resolves to the
same path as the build workspace. cp -r fails with "same file" error
which aborts the build under set -e. Use rsync instead (handles
same-src/dest gracefully), with cp fallback + || true.

This was the root cause of CI build #373 failure.

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

image-recipe/build-auto-installer-iso.sh

@@ -985,7 +985,12 @@ for AIUI_DIR in \
     if [ -d "$AIUI_DIR" ] && [ -f "$AIUI_DIR/index.html" ]; then
         echo "   Including AIUI from $AIUI_DIR..."
         mkdir -p "$ARCH_DIR/web-ui/aiui"
-        cp -r "$AIUI_DIR/"* "$ARCH_DIR/web-ui/aiui/"
+        # Use rsync to handle same-file (CI workspace == /opt/archipelago) gracefully
+        if command -v rsync >/dev/null 2>&1; then
+            rsync -a "$AIUI_DIR/" "$ARCH_DIR/web-ui/aiui/"
+        else
+            cp -r "$AIUI_DIR/"* "$ARCH_DIR/web-ui/aiui/" 2>/dev/null || true
+        fi
         echo "   ✅ AIUI included ($(du -sh "$ARCH_DIR/web-ui/aiui" | cut -f1))"
         AIUI_INCLUDED=1
         break