Implement heuristic ctx restrictive mode

[enaix]

Currently, ContextManager is working in permissive mode. This PR enables the restrictive mode, it will be merged once it's guaranteed to not break things

[enaix]

Current TODO:

• Make prefix/postfix elimination rules well-defined, since now this behavior is random (encountered max_pre -> reduced). This branch should instead check if the heuristic has guessed the prefix correctly (not now)
• Fix the case where equal prefix/postfix is not applied correctly (json member)
• Improve the restrictive mode (check if the symbol is present in the prefix/postfix, use full rr tree)
• Implement a different ambiguous fix todo resolver, since the current one is broken (it just checks everything literally)
• Check terms map again (~) symbol
• Set context[root]=1 during init

[enaix]

In fact, the previous ctx_mgr check_ctx function was broken due to the incorrect indices in rr tree