Currently, custom nodes can only be added as community nodes, which users must install manually. Is there a way to add custom nodes so they are treated as official nodes and available by default without requiring installation?
No not really.
If the team wants to add your node to the official package they will let you know.
You can get your nodes verified, so they are also useable on cloud.
I have published custom nodes on n8n and have got it verified, it means it will be available to any n8n instance , self hosted or n8n.
Check this out , Search for “PDF Api Hub“ my node should come up.
You need to go through verification process , usually 6 weeks to get your node approved.
Here is how you can submit