Cleanup gameplay stats code/UI and support RTA timing (#2862)

soh/include/z64save.h

@@ -83,6 +83,8 @@ typedef struct {
     /*      */ u32 entrancesDiscovered[SAVEFILE_ENTRANCES_DISCOVERED_IDX_COUNT];
     /*      */ u32 scenesDiscovered[SAVEFILE_SCENES_DISCOVERED_IDX_COUNT];
     /*      */ u8 locationsSkipped[RC_MAX];
+    /*      */ bool rtaTiming;
+    /*      */ uint64_t fileCreatedAt;
 } SohStats;
 
 typedef struct {