refactor(sonar): more small fixes

- std::format instead of iostream manipulators in to_string/to_hex_str (cpp:S6495);
  output verified identical, negative hex values keep the unsigned form
- remove an empty compound statement (cpp:S108)
- drop an always-false unsigned < 0 branch (cpp:S1768)
- explicit lambda capture (cpp:S3608)
- std::make_unique (cpp:S5950)

application/driverhints.cpp

@@ -38,7 +38,7 @@ void
 TController::remove_hint( driver_hint const Value ) {
 
     m_hints.remove_if(
-        [=]( auto const &Hint ) {
+        [Value]( auto const &Hint ) {
             return std::get<driver_hint>(Hint) == Value; } );
 }