feat: synced blocks (transclusion) (#2163)

* feat: synced blocks (transclusion)

* fix:remove name

* make placeholders smaller

* feat: enforce strict transclusion schema

* fix: scope synced blocks to workspace, gate unsync on edit permission

* fix collab module error

apps/client/src/features/editor/components/transclusion/transclusion-content.tsx

@@ -0,0 +1,48 @@
+import { EditorProvider } from "@tiptap/react";
+import { useMemo } from "react";
+import { mainExtensions } from "@/features/editor/extensions/extensions";
+import { UniqueID } from "@docmost/editor-ext";
+
+type Props = {
+  content: unknown;
+};
+
+export default function TransclusionContent({ content }: Props) {
+  const extensions = useMemo(() => {
+    const filtered = mainExtensions.filter(
+      (e: any) => e.name !== "uniqueID" && e.name !== "globalDragHandle",
+    );
+    return [
+      ...filtered,
+      UniqueID.configure({
+        types: ["heading", "paragraph", "transclusionSource"],
+        updateDocument: false,
+      }),
+    ];
+  }, []);
+
+  // Isolate the nested read-only editor's events from the host editor:
+  // - mousedown/click would otherwise make the host node-select the atom
+  //   wrapper, blocking native text selection inside.
+  // - dragstart/dragover/drop would otherwise let the host treat events
+  //   inside the nested view as drops on the host, duplicating dropped
+  //   files at the transclusion's position.
+  const stop = (e: React.SyntheticEvent) => e.stopPropagation();
+
+  return (
+    <div
+      onMouseDown={stop}
+      onClick={stop}
+      onDragStart={stop}
+      onDragOver={stop}
+      onDrop={stop}
+    >
+      <EditorProvider
+        editable={false}
+        immediatelyRender={true}
+        extensions={extensions}
+        content={content as any}
+      />
+    </div>
+  );
+}