fix: improve goView iframe detection and locked selection parity

packages/editor/src/editor/Canvas.tsx

@@ -465,7 +465,7 @@ export function Canvas(props: CanvasProps) {
                 if (props.selectionIds.includes(node.id)) {
                   if (node.locked) {
                     // Locked nodes are selectable, but should not start a move drag.
-                    props.onSelectSingle(node.id);
+                    // Keep the current selection intact for multi-select parity.
                     return;
                   }
                   props.onBeginMove(e);

packages/sdk/src/core/goview/convert.ts

@@ -182,7 +182,12 @@ function looksLikeIframeOption(option: unknown): boolean {
   // If it isn't an obvious media URL, it's often an iframe/embed.
   // (We deliberately keep this conservative; image/video are handled earlier.)
   return (
-    (/^https?:\/\//i.test(url) || /^data:text\/html/i.test(url)) &&
+    (
+      /^https?:\/\//i.test(url) ||
+      // protocol-relative URLs (//example.com)
+      /^\/\//.test(url) ||
+      /^data:text\/html/i.test(url)
+    ) &&
     !/\.(png|jpe?g|gif|webp|bmp|svg)(\?|#|$)/i.test(url) &&
     // Avoid misclassifying video streams as iframes.
     !/\.(mp4|m3u8|flv|webm|mov|m4v|ogv)(\?|#|$)/i.test(url) &&