refactor(cli): improve handling of sync version from arguments

[jansegre]

Motivation

It's getting harder to use sync-v1 in practice, might be time to switch the default to sync-v2.

Acceptance Criteria

• Remove --sync-v2-only since it hasn't been released yet
• Add --x-sync-v1-only
• Hide --x-sync-2-only (default) and --x-sync-bridge (already replaced by --sync-bridge)
• Refactor sync-choice logic to make it easier to understand
• Add more tests to cover all sync version parameters

Checklist

• If you are requesting a merge into master, confirm this code is production-ready and can be included in future releases as soon as it gets merged

[codecov]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (8b13de7) 85.32% compared to head (d4699f9) 85.33%.
Report is 1 commits behind head on master.

❗ Current head d4699f9 differs from pull request most recent head 08f1bd4. Consider uploading reports for the commit 08f1bd4 to get more accurate results

Files	Patch %	Lines
hathor/builder/cli_builder.py	96.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #943   +/-   ##
=======================================
  Coverage   85.32%   85.33%           
=======================================
  Files         290      290           
  Lines       22477    22495   +18     
  Branches     3380     3385    +5     
=======================================
+ Hits        19179    19196   +17     
  Misses       2626     2626           
- Partials      672      673    +1     

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