Implement scale factor aware rendering

[RobertBrewitz]

Vello rendering is not DPI or scale factor aware at this time, e.g. on retina displays, most if not all "renderables" will appear smaller than they should be.

Referece material for implementation:

• bevy_vello/src/renderer/extract.rs

  Line 112 in 14375fc

  pub struct ExtractedPixelScale(pub f32);

• https://github.com/bevyengine/bevy/blob/3cefe82aff8ddb018db13b86e514da451a88319f/crates/bevy_render/src/camera/camera.rs#L890
• https://github.com/bevyengine/bevy/blob/3cefe82aff8ddb018db13b86e514da451a88319f/crates/bevy_render/src/camera/camera.rs#L950