Restrict usages of type variables in non-generalized contexts #3019

Job	Run time
check-changes	23s
ran-none	0s
start-nix-linux-x86-64-tests / nix-linux-x86	2m 44s
start-nix-macos-apple-silicon-tests / nix-apple-silicon	1s
start-nix-linux-aarch64-build-default-test / nix-linux-arm64	2m 42s
start-nix-linux-aarch64-cargo-build-test / nix-linux-arm64	2m 43s
start-macos-x86-64-tests / test-rust-macos-x86-64	2m 44s
start-ubuntu-x86-64-nix-tests-debug / cargo test debug nix	2m 39s
start-ubuntu-x86-64-tests / test zig, rust, wasm...	2m 44s
start-fuzzer-tests / Fuzz test parser (allowed to fail). Do check this if you've made changes to the parser.	1s
start-roc-benchmarks / benchmark roc programs	1s
start-windows-release-build-test / windows-release-build	2m 24s
start-windows-tests / windows-test-subset	2m 20s
ran-full	1s
finish	1s
	21m 28s

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