Restructure auto-sync docs to have them more contained

[Rot127]

Your checklist for this pull request

• I've documented or updated the documentation of every API function and struct this PR changes.
• I've added tests that prove my fix is effective or that my feature works (if possible)

Detailed description

The auto-sync documentation was spread around and confusing. This is an attempt to move it closer together and remove duplicate (and contradicting) instructions.

Todo

• Add a section about "Why we need actually auto-sync". Possibly take it from the blog post.
• A Link to (archived) blog post for deep dives
• Extend the main ARCHITECTURE.md for the Capstone section
  • A Link it on the main README and make it clear that it is a "must" first read for any developer.
• Add tldr version about TableGen from the blog post somewhere.

Test plan

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Closing issues

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