first pass at asynchronous file streaming -> hash store layer; fix non-windowed memory access in watch window when doing change visualization, causing major performance regression with large arrays; fix some extra jank with truncated-string-hover & help labels

src/ui/ui_core.c

@@ -1335,6 +1335,10 @@ ui_end_build(void)
             goto break_all_hover_string;
           }
         }
+        if(b != box && contains_2f32(b->rect, ui_state->mouse))
+        {
+          goto break_all_hover_string;
+        }
       }
     }
     break_all_hover_string:;