How to store cache block id to the rax tree?

[vegetableysm]

Describe your problem

Currently, the rax tree stored the cache block builder pointer for user requests. It can not serialize to vineyardd and use by other client. However, the object id can only be obtained after calling the seal function. So we can not set the object id when create sub tree. How to replace the builder pointer with the builder object id before serialize the tree?

Additional context

Add any other context about the problem here.