Display tessellation plans (3/4): display meshes from plans, GPU evaluation in the viewport (#805)

Display meshes are built from tessellation plans, with GPU evaluation in the viewport.

Cargo.toml

@@ -18,6 +18,7 @@ solidcraft-geom = { path = "crates/geom" }
 solidcraft-sketch = { path = "crates/sketch" }
 solidcraft-kernel = { path = "crates/kernel" }
 solidcraft-render = { path = "crates/render" }
+solidcraft-gpu = { path = "crates/gpu" }
 solidcraft-doc = { path = "crates/doc" }
 solidcraft-io = { path = "crates/io" }
 solidcraft-engine = { path = "crates/engine" }
@@ -58,6 +59,9 @@ eframe = { version = "0.36", default-features = false, features = ["persistence"
 # Instant/SystemTime that also work in the browser (std panics on wasm32-unknown-unknown).
 web-time = "1"
 egui-wgpu = "0.36"
+# the wgpu egui-wgpu uses, for compute (crates/gpu); backends come from the apps' features
+wgpu = { version = "30", default-features = false, features = ["std", "wgsl"] }
+pollster = "0.4"
 rfd = "0.17"
 
 [workspace.lints.rust]