🐛(frontend) fix callout block cursor position

Disabled the "gapCursor" prosemirror extension on the editor.
Cursor gets to non text positions around custom blocks, in this case the
callout block, which is a feature of the "gapCursor" extension.

Author: ZouicheOmar

src/frontend/apps/impress/src/features/docs/doc-editor/components/BlockNoteEditor.tsx

@@ -125,6 +125,7 @@ export const BlockNoteEditor = ({ doc, provider }: BlockNoteEditorProps) => {
       },
       uploadFile,
       schema: blockNoteSchema,
+      disableExtensions: ['gapCursor'],
     },
     [collabName, lang, provider, uploadFile],
   );