Cache tools and Rust build output in CI and release builds

scripts/ci-setup.sh

@@ -16,6 +16,9 @@ fi
 $SUDO apt-get update -q
 $SUDO apt-get install -yq --no-install-recommends "${packages[@]}"
 
+# Rust, cargo-xwin and mise may already be here from the CI cache.
+export PATH="$HOME/.cargo/bin:$HOME/.local/bin:$PATH"
+
 # Rust: not pinned in mise.toml, because mise needs rustup for it.
 if ! command -v cargo >/dev/null; then
   curl -fsSL https://sh.rustup.rs | sh -s -- -y --profile minimal
@@ -25,10 +28,10 @@ export PATH="$HOME/.cargo/bin:$PATH"
 
 if [[ "${1:-}" == "--windows" ]]; then
   rustup target add x86_64-pc-windows-msvc
-  cargo install --locked cargo-xwin
+  command -v cargo-xwin >/dev/null || cargo install --locked cargo-xwin
 fi
 
-curl -fsSL https://mise.run | MISE_VERSION=v2026.9.1 sh
+command -v mise >/dev/null || curl -fsSL https://mise.run | MISE_VERSION=v2026.9.1 sh
 echo "$HOME/.local/bin" >> "$GITHUB_PATH"
 echo "$HOME/.local/share/mise/shims" >> "$GITHUB_PATH"
 export PATH="$HOME/.local/bin:$HOME/.local/share/mise/shims:$PATH"