* flush queues on portal close
* fix mouse broadcast race condition
* stop mutating image elements when updating status
to fix race condition when closing/opening collab room
* check `files` when resolving `LayerUI`
* fix displaying AbortError
* feat: support exporting json to excalidraw plus
* add Firebase Storage rules to codebase
* factor the onClick handler out
* move excal icon to icons.tsx
* handle export error
