feat: update proposal snapshots handling on block (forbole#523)

Closes: #XXXX

<!-- Add a description of the changes that this PR introduces and the
files that
are the most critical to review. -->

---

*All items are required. Please add a note to the item if the item is
not applicable and
please add links to any relevant follow up issues.*

I have...

- [x] included the correct [type
prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json)
in the PR title
- [x] added `!` to the type prefix if API or client breaking change
- [x] targeted the correct branch
- [ ] provided a link to the relevant issue or specification
- [x] added a changelog entry to `CHANGELOG.md`
- [x] included comments for [documenting Go
code](https://blog.golang.org/godoc)
- [x] updated the relevant documentation or specification
- [x] reviewed "Files changed" and left comments if necessary
- [x] confirmed all CI checks have passed

*All items are required. Please add a note if the item is not applicable
and please add
your handle next to the items reviewed if you only reviewed selected
items.*

I have...

- [ ] confirmed the correct [type
prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json)
in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)