Return `in_view: bool` from `Viz.update_graphics()`

Allows callers to know if they should care about a particular viz
rendering call by immediately knowing if the graphics are in view. This
turns out super useful particularly when doing dynamic y-ranging overlay
calcs.

piker/ui/_dataviz.py

@@ -1061,7 +1061,7 @@ class Viz(msgspec.Struct):  # , frozen=True):
 
             else:
                 log.warning(f'Unknown view state {vl} -> {vr}')
-                return
+                # return
                 # raise RuntimeError(f'Unknown view state {vl} -> {vr}')
 
         else:

piker/ui/_fsp.py

@@ -707,7 +707,7 @@ async def open_vlm_displays(
 
         last_val_sticky.update_from_data(-1, value)
 
-        _, vlm_curve = vlm_viz.update_graphics()
+        _, _, vlm_curve = vlm_viz.update_graphics()
 
         # size view to data once at outset
         vlm_chart.view._set_yrange(