feat: aes 287 create conclusion event type (#499)

* feat: add new crate for conclusion-event

* feat: add unit test for conversion + fix timestamp to accept nullable

* chore: cleanup

* fix: docstring + cargo.toml name

* fix: review comments

* fix: doc strings

* chore: remove streamType + fix: make method accept an iterator use extend trait

* fix: remove unused dep

* chore: cleanup

* chore: use StreamIDType in tests

* feat: implement Conclusions time + added stream_cid to Conclusion events

* chore: use expect test in test cases

* chore: add test for time events

* fix: test to use string cid and do actual chaining

* chore: update lockfile

* fix: update console-subscriber

* fix: use datafusion apis to convert cid bytes to string

* fix: update cargo.lock

* chore: formatting

* chore: remove commented lines

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Co-authored-by: Samika Kashyap <[email protected]>