feat(code)!: Decouple Host messages from Consensus actor

[romac]

Closes: #XXX

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PR author checklist

For all contributors

• Reference a GitHub issue
• Ensure the PR title follows the conventional commits spec
• Add a release note in RELEASE_NOTES.md if the change warrants it
• Add an entry in BREAKING_CHANGES.md if the change warrants it

For external contributors

• Maintainers of Malachite are allowed to push changes to the branch

[codecov]

Codecov Report

Attention: Patch coverage is 82.25806% with 11 lines in your changes missing coverage. Please review.

Project coverage is 75.21%. Comparing base (1ff5b8c) to head (a269d47).

✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1109      +/-   ##
==========================================
- Coverage   75.56%   75.21%   -0.35%     
==========================================
  Files         170      170              
  Lines       17945    17932      -13     
  Branches    17945    17932      -13     
==========================================
- Hits        13560    13487      -73     
- Misses       3498     3570      +72     
+ Partials      887      875      -12     

Flag	Coverage Δ
integration	75.01% <82.26%> (-0.36%)	⬇️
mbt	7.67% <0.00%> (-<0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
core	82.44% <ø> (-0.02%)	⬇️
engine	72.23% <93.94%> (+0.16%)	⬆️
app	85.46% <64.71%> (-1.44%)	⬇️
starknet	73.45% <70.00%> (-0.10%)	⬇️

[github-actions]

✅ Semver Check Passed

Great job! All semver violations have been resolved. This PR now complies with semantic versioning rules.

If you made version updates, please ensure that:

• The version in Cargo.toml accurately reflects the nature of your changes
• Any breaking changes are properly documented in BREAKING_CHANGES.md

[sergio-mena]

I like these changes. They will simplify the readability of TestConsensus in Muppet 🚀

[romac]

@ancazamfir @hvanz Any concerns with merging this?

[ancazamfir]

@ancazamfir @hvanz Any concerns with merging this?

Looks good!