literals true/false are not necessarily created when the merge flag is set.
Also disable merge_tf for if-then-else expressions
Perhaps even not insert children of if expressions into congruence table?
perf fix for propagation behavior for equalities in the new core.
The old behavior was not to allow congruence closure on equalities.
The new behavior is to just not allow merging tf with equalities unless they appear somewhere in a foreign context (not under a Boolean operator)
The change re-surfaces merge_tf and enable_cgc distinction from the old core.
They can both be turned on or off.
merge_enabled renamed to cgc_enabled
The change is highly likely to introduce regressions in the new core.
Change propagation of literals from congruence:
- track antecedent enode. There are four ways to propagate
literals from the egraph.
- the literal is an equality and the two arguments are congruent
- the antecedent is merged with node n and the antecedent has a Boolean variable assignment.
- the antecedent is true or false, they are merged.
- the merge_tf flag is toggled to true but the node n has not been merged with true/false
log theory propagations with annotation "smt".
It allows tracking theory propagations (when used in conflicts) in the clause logs similar to the new core.
this update breaks use cases that set sat.smt.proof to True.
As it is such a new feature and the change affects possibly at most the tutorial it is made without compatibility layers.
this is to enable use cases like:
```
from z3 import *
s = Solver()
OnClause(s, print)
s.set("solver.proof.check", False)
s.from_file("../satproof.smt2")
```
instead of setting global parameters before the proof replay is initialized.
