Feature request: remove need for intermediate pl calls when chaining renderers

Description of feature

Thanks for the super nice work, @timtreis and @sagar87 ! I think it would be nice if we didn't have to add intermediate calls to pl when chaining renderers. That is, I think it would be nice if instead of this:

sdata.pl.render_images().pl.render_shapes().pl.show()

We could do this:

sdata.pl.render_images().render_shapes().show()

This perhaps could be possible if the render_*() methods returned the plot accessor instead of the SpatialData object. I suppose this means that one couldn't do a pp operation after a pl operation, but maybe that suggests the pl and pp operations should be on the same level of the hierarchy or one should do their preprocessing first, then their plotting. I'm not sure what's best here, but it might be good to experiment with this once all of the p0 functionality is finished.

首先检查 pl accessor 和 render_* 方法，特别是它们当前如何返回 SpatialData 以及支持链式调用。将现有示例 sdata.pl.render_images().pl.render_shapes().pl.show() 与提议的链式行为进行比较，并确定 pl 和 pp 操作应如何交互。完成的标准是确定 API 设计，并实现无需中间 pl 调用的 renderer 链式调用。