Refactor mk_and and mk_app to use std::span API (#8285)

* Initial plan

* Refactor mk_and and mk_app to use std::span

- Made mk_and(unsigned num_args, expr * const * args) private
- Added new public mk_and(std::span<expr* const> args) method
- Added new public mk_app(family_id fid, decl_kind k, std::span<expr* const> args) method
- Updated all convenience overloads to use std::span version
- Updated all external call sites to use the new std::span API

Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>

* Fix remaining test files to use std::span API

- Updated src/test/sorting_network.cpp
- Updated src/test/ho_matcher.cpp with explicit cast to resolve ambiguity

Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>

* Revert overlapping changes superseded by PR #8286

Reverted 30 files to match the state from PR #8286 (commit ebc0688) which refactored mk_and/mk_or call sites to use vector overloads. This supersedes the std::span changes in those files.

Retained std::span changes in files unique to this PR:
- Core API changes (ast.h, ast.cpp)
- Files not affected by PR #8286 (api_context.cpp, ast_util.cpp, bool_rewriter.h, datatype_rewriter.cpp, dom_simplifier.cpp, factor_rewriter.cpp, pb2bv_rewriter.cpp, quant_hoist.cpp, spacer_cluster_util.cpp, sortmax.cpp, array_axioms.cpp, smtfd_solver.cpp, goal.cpp, ho_matcher.cpp, qe_arith.cpp, sorting_network.cpp)
- Special case in hnf.cpp where both PRs modified different lines

Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: NikolajBjorner <3085284+NikolajBjorner@users.noreply.github.com>

src/muz/base/hnf.cpp

@@ -274,7 +274,7 @@ private:
 
             if (premise) {
                 expr_ref f1 = bind_variables(mk_implies(m_body, head));
-                expr* f2 = m.mk_and(sz, m_todo.data()+m_todo.size()-sz);
+                expr* f2 = m.mk_and(std::span<expr* const>(m_todo.data()+m_todo.size()-sz, sz));
                 proof_ref p2(m), p3(m);
                 p2 = m.mk_def_axiom(m.mk_iff(f1, f2));
                 p3 = mk_quant_intro(fml, f1, p);                    

src/muz/spacer/spacer_cluster_util.cpp

@@ -178,7 +178,7 @@ struct term_ordered_rpp : public default_rewriter_cfg {
             kids.append(num, args);
             std::stable_sort(kids.data(), kids.data() + kids.size(),
                              m_and_less);
-            result = m.mk_and(num, kids.data());
+            result = m.mk_and(std::span<expr* const>(kids.data(), num));
             return BR_DONE;
         }
         return st;