adjust conversion visualization; strip out old profiling markup

src/df/core/df_core.c

@@ -1802,6 +1802,7 @@ df_entity_alloc(DF_StateDeltaHistory *hist, DF_Entity *parent, DF_EntityKind kin
   df_state->entities_id_gen += 1;
   entity->id = df_state->entities_id_gen;
   entity->generation += 1;
+  entity->alloc_time_us = os_now_microseconds();
   
   // rjf: dirtify caches
   df_state->kind_alloc_gens[kind] += 1;

src/df/core/df_core.h

@@ -430,6 +430,7 @@ struct DF_Entity
   DF_EntityFlags flags;
   DF_EntityID id;
   U64 generation;
+  U64 alloc_time_us;
   B32 deleted;
   F32 alive_t;
   
@@ -1226,6 +1227,7 @@ read_only global DF_Entity df_g_nil_entity =
   0,
   0,
   0,
+  0,
   
   // rjf: allocationless, simple equipment
   {0},