[P2][Stateless validation] Better coordination between chunk distribution and state witness distribution

[walnut-the-cat]

There seems to be significant amount of data overlap (e.g. source receipt) between chunk distribution and state witness distribution. We need to have holistic look on how both works so we can leverage both distribution mechanisms for efficiency.

Relevant discussion can be found here: https://near.zulipchat.com/#narrow/stream/407237-core.2Fstateless-validation/topic/.E2.9C.94.20Chunk.20distribution.20and.20Stateless.20validation/near/432285623