Add serialization for consumption history

So that monotony penalties carry over upon save/load.

src/character.h

@@ -182,13 +182,15 @@ struct social_modifiers {
 struct consumption_event {
     time_point time;
     itype_id type_id;
-    uint64_t component_hash = 0;
+    uint64_t component_hash;
 
-    consumption_event( const item &food ) {
-        time = calendar::turn;
+    consumption_event() = default;
+    consumption_event( const item &food ) : time( calendar::turn ) {
         type_id = food.typeId();
         component_hash = food.make_component_hash();
     }
+    void serialize( JsonOut &json ) const;
+    void deserialize( JsonIn &jsin );
 };
 
 inline social_modifiers operator+( social_modifiers lhs, const social_modifiers &rhs )
@@ -681,6 +683,9 @@ class Character : public Creature, public visitable<Character>
                           const item &new_item ) const;
 
         std::array<std::array<int, NUM_WATER_TOLERANCE>, num_bp> mut_drench;
+
+        void serialize_consumption_history( JsonOut jsout ) const;
+        void deserialize_consumption_history( JsonArray jarr );
     public:
         // recalculates enchantment cache by iterating through all held, worn, and wielded items
         void recalculate_enchantment_cache();

src/savegame_json.cpp

@@ -390,6 +390,23 @@ void Character::trait_data::deserialize( JsonIn &jsin )
     data.read( "powered", powered );
 }
 
+void consumption_event::serialize( JsonOut &json ) const
+{
+    json.start_object();
+    json.member( "time", time );
+    json.member( "type_id", type_id );
+    json.member( "component_hash", component_hash );
+    json.end_object();
+}
+
+void consumption_event::deserialize( JsonIn &jsin )
+{
+    JsonObject jo = jsin.get_object();
+    jo.read( "time", time );
+    jo.read( "type_id", type_id );
+    jo.read( "component_hash", component_hash );
+}
+
 /**
  * Gather variables for saving. These variables are common to both the avatar and NPCs.
  */
@@ -453,6 +470,7 @@ void Character::load( const JsonObject &data )
         lvl = std::max( std::min( lvl, v.first.obj().max() ), v.first.obj().min() );
         vitamin_levels[v.first] = lvl;
     }
+    data.read( "consumption_history", consumption_history );
     data.read( "activity", activity );
     data.read( "destination_activity", destination_activity );
     data.read( "stashed_outbounds_activity", stashed_outbounds_activity );
@@ -693,6 +711,7 @@ void Character::store( JsonOut &json ) const
     json.member( "vitamin_levels", vitamin_levels );
     json.member( "pkill", pkill );
     json.member( "omt_path", omt_path );
+    json.member( "consumption_history", consumption_history );
 
     // crafting etc
     json.member( "destination_activity", destination_activity );