fix bug in new core not detecting conflict, fix #6525, add tactic doc

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/smt/tactic/ctx_solver_simplify_tactic.h

@@ -13,7 +13,17 @@ Author:
 
     Nikolaj (nbjorner) 2012-3-6
 
-Notes:
+Tactic Documentation:
+
+## Tactic ctx-solver-simplify
+
+### Short Description
+
+A heavy handed version of `ctx-simplify`. It applies SMT checks on sub-formulas to check
+if they can be simplified to `true` or `false` within their context.
+Note that a sub-formula may occur within multiple contexts due to shared sub-terms.
+In this case the tactic is partial and simplifies a limited number of context occurrences.
+
 
 --*/
 #pragma once

src/smt/tactic/unit_subsumption_tactic.h

@@ -13,12 +13,20 @@ Author:
 
     Nikolaj Bjorner (nbjorner) 2012-9-6
 
-Notes:
+Tactic Documentation:
 
-    Background: PDR generates several clauses that subsume each-other.
-    Simplify a goal assuming it is a conjunction of clauses.
-    Subsumed clauses are simplified by using unit-propagation 
-    It uses the smt_context for the solver.
+## Tactic unit-subsume-simplify
+
+### Short Description
+
+implify goal using subsumption based on unit propagation
+
+### Long Description
+
+Background: PDR generates several clauses that subsume each-other.
+Simplify a goal assuming it is a conjunction of clauses.
+Subsumed clauses are simplified by using unit-propagation 
+It uses the default SMT solver.
 
 --*/
 #pragma once