Replace empty destructors with = default for compiler optimization (#8189)

* Initial plan

* Replace empty destructors with = default

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/sat/sat_ddfw_wrapper.h

@@ -37,7 +37,7 @@ namespace sat {
 
         ddfw_wrapper() {}
         
-        ~ddfw_wrapper() override {}
+        ~ddfw_wrapper() override = default;
 
         void set_plugin(local_search_plugin* p) { m_ddfw.set_plugin(p); }
 

src/sat/sat_drat.h

@@ -29,7 +29,7 @@ namespace sat {
     class clause;
 
     struct clause_eh {
-        virtual ~clause_eh() {}
+        virtual ~clause_eh() = default;
         virtual void on_clause(unsigned, literal const*, status) = 0;        
     };
 

src/sat/sat_types.h

@@ -96,7 +96,7 @@ namespace sat {
 
     class proof_hint {
     public:
-        virtual ~proof_hint() {}
+        virtual ~proof_hint() = default;
     };
 
     class status {

src/sat/smt/euf_proof_checker.h

@@ -31,7 +31,7 @@ namespace euf {
 
     class theory_checker_plugin {
     public:
-        virtual ~theory_checker_plugin() {}
+        virtual ~theory_checker_plugin() = default;
         virtual bool check(app* jst) = 0;
         virtual expr_ref_vector clause(app* jst) = 0;
         virtual void register_plugins(theory_checker& pc) = 0;