Changed auto focus slightly

https://github.com/ocornut/imgui/issues/4054 seems to be the relevant
issue. I'm not sure what I can really do about fixing it. This fix
doesn't quite give me the behavior I want.

src/FileHelper.cake

@@ -681,8 +681,10 @@
   ;;   (set (field imgui-io KeyRepeatRate) 0.3f))
 
   (when (path state > focus-filter)
-    ;; (imgui-call SetKeyboardFocusHere)
+    (unless (imgui-call IsAnyItemActive)
+      (imgui-call SetKeyboardFocusHere))
     (set (path state > focus-filter) false))
+
   (call-on Draw (path state > directory-filter))
 
   ;; Update the actual list immediately after the filter