fix: make fendermint blobs types public

[joewagner]

The changes in #582 moved the AccountInfo type from the fendermint_blobs_shared packages to the fendermint_blobs package. This type is needed by the rust SDK, and the move made the type private.
The change in this PR makes the fendermint_blobs::state module public, so the SDK can access it.
Related PR for the SDK is here: recallnet/rust-recall#256

[sanderpick]

possible to just move it back to shared? or we can fix later

[joewagner]

cc: @sam701

[joewagner]

possible to just move it back to shared? or we can fix later

For sure. I almost did that, but wasn't sure if there was a reason it got moved.

[joewagner]

@sanderpick I moved the type back to shared, assuming CI passes, this makes the SDK work without any changes, so recallnet/rust-recall#256 can be closed.
Does this look good?

[sanderpick]

looks good to me but @ukstv what do you think? not sure if you had a reason for the move

[ukstv]

Started writing this: "The reason for the move was that it uses to_delegated_address of the recall_actor_sdk which supposedly should work only inside a WASM actor. That might lead to a problem later, because of...." And then I realized it does not make any sense. So LGTM.

The original reason was somehow related to to_delegated_address fn, but I do not recall what was that.