Provide a built-in way to generate set of entities having relationships between each others

[dubzzz]

💡 Idea

Generating structures being tied to one another in a many-to-many or one-to-many relationship in fast-check is not trivial. While feasible it requires our users to come up with advanced and complex options. The two tickets below are asking for it:

• https://github.com/dubzzz/fast-check/discussions/5022
• https://github.com/dubzzz/fast-check/discussions/5023

As the case is pretty general, we should probably come up with a built-in utility hiding all this complexity and able to generate a simple database content based on a provided schema. The helpers for many-to-many and many-to-one initiated by @gruhn sounds like great ideas to start to think of it.

Disclaimer: while the issue has been opened, there is no certainty that there will be a built-in helpers for that purpose, but at least we can start thinking of it: api, implem...