Polysat: fixes in solver, forbidden intervals for eq_constraint (#5240)

* Rename to neg_cond

* Add some logging utilities

* Implement case of forbidden interval covering the whole domain

* Implement diseq_narrow

* Do not activate constraint if we are in a conflict state

* comments

* Assert that lemma isn't undefined

* Update revert_decision to work in the case where narrowing causes propagation

* Fix case of non-disjunctive lemma from forbidden intervals

* Conflict should not leak outside user scope

* Add guard to decide(), some notes

* Add test case

* Add constraints to watchlist of unassigned variable during propagation

* Move common propagation functionality into base class

* Combine eq/diseq narrow

* Compute forbidden interval for equality constraints by considering them as p <=u 0 (or p >u 0 for disequalities)

src/util/scoped_ptr_vector.h

@@ -87,6 +87,8 @@ public:
         return tmp;
     }
 
+    T* const* data() const { return m_vector.data(); }
+
     using const_iterator = typename ptr_vector<T>::const_iterator;
     const_iterator begin() const { return m_vector.begin(); }
     const_iterator end() const { return m_vector.end(); }