Bugfix/partially cyclic evaluation

[phi1010]

Bugfix written with Fable5 alone, and unit tests for the edgecases it fixes.
Code not yet verified by a Rust developer, might cause unintended side effects the tests don't cover.
Please review thouroughly as discussed in #743

[phi1010]

@microsoft-github-policy-service agree

[phi1010]

This is still incomplete, it does not reject all recursions in doubt:

import textwrap

import regorus
from icecream import ic


def run():

    eng = regorus.Engine()
    eng.add_policy(
        "recursion.rego",
        textwrap.dedent(
            """
            package foo
            import rego.v1
            a := [input.x,i] if {
                i:=a with input as { "x": input.x+1 }
            }    
            """),
    )
    ic(eng.eval_query("data"))

if __name__ == "__main__":
    run()

$ ./rego-recursion.py 
ic| eng.eval_query("data"): {'result': [{'bindings': {},
                                         'expressions': [{'location': {'col': 1, 'row': 1},
                                                          'text': 'data',
                                                          'value': {'foo': {}}}]}]}


$ opa eval --data test.rego  "data"
{
  "errors": [
    {
      "message": "rule data.foo.a is recursive: data.foo.a -\u003e data.foo.a",
      "code": "rego_recursion_error",
      "location": {
        "file": "test.rego",
        "row": 3,
        "col": 13
      }
    }
  ]
}

[anakrish]

@phi1010 Can you also address the RVM flow in this PR? Currently the fix only targets the interpreter.

I will free up next week and should be able to devote more time to this.