[Simulation] In-place creation of mechanical visitors

[alxbilger]

Modern and flexible creation of the usual mechanical visitors at the call site. It uses the function makeMechanicalVisitor.
An example of use.

Pros:

• No more back-and-forth between the call site and the visitor file. The intention can be read clearly at the call site.
• Dozens of visitor files can be removed

Cons:

• A bit of template meta-programming
• Some ugly macros
• More code at the call site (but it's so much clearer so it's not a con😄 )

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Reviewers will merge this pull-request only if

• it builds with SUCCESS for all platforms on the CI.
• it does not generate new warnings.
• it does not generate new unit test failures.
• it does not generate new scene test failures.
• it does not break API compatibility.
• it is more than 1 week old (or has fast-merge label).

[alxbilger]

[ci-build][with-all-tests]