chore: take the stack without nalgebra

The codec declared nalgebra and never used it — its Vector2 and Vector3
are plain structs of its own. It was pulling eleven crates into every
build here for nothing.

Also picks up cadkernel's Vec2, which replaces the vector arithmetic the
kernel had been writing out by hand.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

crates/ocs_web_worker/Cargo.toml

@@ -8,7 +8,7 @@ publish = false
 crate-type = ["cdylib"]
 
 [dependencies]
-acadrust = { package = "acadifc", git = "https://github.com/OpenAEC-Foundation/acadifc.git", rev = "0a61cf9", features = ["serde"] }
+acadrust = { package = "acadifc", git = "https://github.com/OpenAEC-Foundation/acadifc.git", rev = "c65d396", features = ["serde"] }
 bincode = "1.3"
 console_error_panic_hook = "0.1"
 getrandom = { version = "0.3", features = ["wasm_js"] }