`bevy_extract` tracking

[Zeophlite]

What problem does this solve or what need does it fill?

• Make the extract infra reusable for non-rendering crates, and allow extraction to work for multiple sub-apps

e.g.

// Extract a component from the main subapp to the render subapp, and the audio subapp

#[derive(Component, Clone, Debug, ExtractComponent)]
#[extract_app(RenderApp, AudioApp)]
struct SomeComponent;

How do we get there?

• Move uniform out of extract_component #23372

• Generalise TemporaryRenderEntity over AppLabel #24419

• Be explicit that extraction is to RenderApp for SyncComponent / ExtractComponent / ExtractResource #24420

• Make ExtractComponentPlugin etc. generic on AppLabel #24423

• Extract extract to bevy_extract #22852

• Simplified by Add constraints to AppLabel #23377

What alternative(s) have you considered?

Alternatively, remove extraction entirely. This can be done as followup by rm -rf crates/bevy_extract/ 😄

[Zeophlite]

@atlv24 @kfc35 @kristoff3r Please have a review