Copy timestamps from source to FSP dest buffer

piker/fsp/_engine.py

@@ -179,6 +179,8 @@ async def fsp_compute(
         )
         history[func_name] = history_output
 
+    history['time'] = src.array['time']
+
     # TODO: XXX:
     # THERE'S A BIG BUG HERE WITH THE `index` field since we're
     # prepending a copy of the first value a few times to make