Explain where rendering is

[stepancheg]

It was not easy to find. Add some pointers to the comment.

[alice-i-cecile]

Helpful! It's still a bit weird to me that we're using this struct like a module-level doc comment, but this is a good addition.

[stepancheg]

My reasoning is this. I'm looking at various schedule labels like PostUpdate and Last. Do they perform rendering? Not clear, but they link to the Main schedule. So I go to Main, and this is the end, no more outgoing links.

Perhaps we can only add links to plugins, and move the wall of text to PipelinedRenderingPlugin, before this:

bevy/crates/bevy_render/src/pipelined_rendering.rs

Lines 28 to 38 in d99053c

	/// The [`PipelinedRenderingPlugin`] can be added to your application to enable pipelined rendering.
	/// This moves rendering into a different thread, so that the Nth frame's rendering can
	/// be run at the same time as the N + 1 frame's simulation.
	///
	/// ```text
	/// |--------------------|--------------------|--------------------|--------------------|
	/// | simulation thread | frame 1 simulation | frame 2 simulation | frame 3 simulation |
	/// |--------------------|--------------------|--------------------|--------------------|
	/// | rendering thread | | frame 1 rendering | frame 2 rendering |
	/// |--------------------|--------------------|--------------------|--------------------|
	/// ```

[stepancheg]

Added links to docs.rs, made test in Main shorter, added text to RenderPlugin.