New feat: tci(): tag to trigger the CI

[pascalandy]

• Impact on: PINNED/ TODO and backlog #4, PINNED/ UX Improvements #8
• User facing
• Now, main_branch builds only when pushing tags
• Now, the CI do not build on every commits on main_branch (its a pain when we merge many PRs)
• Sometime we work directly on the main_branch (typically for CI work) and we dont want to trigger the CI pipeline
• Refactor squash() and dummy()