refactor: move /proto/{modules} to their own modules

[julienrbrt]

Description

Closes: #13363, #12003
Implements some ideas from #12003

WIP

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Author Checklist

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• included the correct type prefix in the PR title
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• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
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• confirmed the correct type prefix in the PR title
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• reviewed state machine logic
• reviewed API design and naming
• reviewed documentation is accurate
• reviewed tests and test coverage
• manually tested (if applicable)

[tac0turtle]

Lets not do this till after 0.47 please

[julienrbrt]

Lets not do this till after 0.47 please

Alright! Closing for now!

[alexanderbez]

Love the effort, but yeah let's do it after 0.47 -- good to have a PR as a reference though!