Use the `Animation` data-block to find F-Curves, for drawing the
background color of properties in the GUI (green for 'animated', yellow
for 'keyed on this frame', etc.).
This assumes (correctly) that the `Animation` is limited to a single
layer with a single strip. As such, there is only one set of F-Curves
for every animated ID, which means that the correct F-Curve will be
found. This will need adjustment when the same property can have
multiple F-Curves (due to layers) or when an F-Curve may not be
applicable for each point in time (due to the use of finite strips).
Pull Request: https://projects.blender.org/blender/blender/pulls/118677
694e5b50f4