plugin setting allows adding equality saturation within the E-graph propagation without involving externalizing theory solver dispatch. It makes equality saturation independent of SAT integration.
Add a special relation operator to support ad-hoc AC symbols.
EUF proofs are checked modulo union-find.
Equalities are added to to union-find if they are assumptions or if they can be derived using congruence closure. The congruence closure assumptions are added as proof-hints.
Note that this proof format does not track equality inferences, symmetry and transitivity. Instead they are handled by assuming a union-find based checker.
