Add a complexity limit on displaying layer thumbnails to improve performance (#2828)

* Skip complex layer thumbnails

* Set Raster<GPU> to have usize::MAX render complexity

* Code review

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Co-authored-by: Keavon Chambers <keavon@keavon.com>

node-graph/gcore/src/lib.rs

@@ -22,6 +22,7 @@ pub mod ops;
 pub mod raster;
 pub mod raster_types;
 pub mod registry;
+pub mod render_complexity;
 pub mod structural;
 pub mod text;
 pub mod transform;