Embedding admission strategy

[z52527]

Description

#111 This PR implements the admission strategy in DynamicEmb forward

Checklist

• [ ] I am familiar with the Contributing Guidelines.
• [ ] New or existing tests cover these changes.
• [ ] The documentation is up to date with these changes.

[shijieliu]

@jiashuy @z52527 before we merge this PR, we need to add doc and update example

[z52527]

Track CI here.