This is very useful for test

This is much more readable

We need this for set comparison implemented in 2a175b352c78

The old code did:
* forge a string
* eval it as a lamba
* monkey patch classes with the result

We may just drop the logic looping on multiple class by computing class name
dynamically. But this have a different behavior for subclass.

Use set instead of list for domains. This remove some N² complexity. Simplify
the visite_relation code to:

* avoid computation duplication,
* compare string instead of Yams object,
* take advantage of set.

fix Referencable.get_type crash when no solution given and 'is IN(ET1, ET2..) is used. Closes #81865

668:b2e231cbd9da introduces unrelated changes that 1. break tests, 2. make rql>0.30.1 incompatible with cw < 3.13.10

closes #74727: allow entity types to end with a capitalized letter provided they contain a lower-cased letter

containing HAVING comparison nodes where it's used and optional (eg outer join)

* & (bitwise AND),
* | (bitwise OR),
* # (bitwise XOR),
* << (bitwise left shift),
* >> (bitwise right shift)
* % (modulo),
* ^ (power),