Fix crash when repairing items (#51837)

* Fix crash when repairing items

This was caused by #51600 which pops the current target if cannot_continue_repair is true.
However, this popped target is later used as fix_location (it's a reference set earlier).

This also fixes #51828 and #51674.

* Update src/activity_handlers.cpp

Co-authored-by: Kevin Granade <kevin.granade@gmail.com>

src/activity_handlers.cpp

@@ -2393,7 +2393,8 @@ void activity_handlers::repair_item_finish( player_activity *act, Character *you
         const bool event_happened = attempt == repair_item_actor::AS_FAILURE ||
                                     attempt == repair_item_actor::AS_SUCCESS ||
                                     old_level != you->get_skill_level( actor->used_skill );
-        const bool can_refit = !destroyed && fix_location->has_flag( flag_VARSIZE ) &&
+        const bool can_refit = !destroyed && !cannot_continue_repair &&
+                               fix_location->has_flag( flag_VARSIZE ) &&
                                !fix_location->has_flag( flag_FIT );
 
         const bool need_input =