[Feature Request] Shared code auto code split

[huozhi]

Feedback from users

In the case where I want to share internal modules but not export them from the package, this doesn't work. I see each entry has its own rollup config defined, which would prevent rollup from handling these common chunks on its own. Have you thought about using a single config with separate input declarations for each entry? I would guess that maybe this would allow rollup to handle the common modules on its own.

Need to design a solution for shared modules that doesn't have to go to shared inputs