[Bug]: SSH setup tries to install a nonexistent macOS x64 archive#33314

Problem

SSH setup accepts a Darwin/x86_64 host and attempts to install t3-<version>-darwin-x64.tar.gz. T3 does not publish that archive: the current v0.1.7 release has only t3-0.1.7-darwin-arm64.tar.gz for macOS, and CLI_ARCHIVE_PLATFORM_KEYS explicitly excludes darwin-x64 because Node single-executables do not support it.

The result is an attempted release download instead of the unsupported-platform explanation already used for other unsupported hosts.

Reproduction and evidence

Found on main at 2b65ffb641f152fadf443096bad7f4a0677caae4 in packages/ssh/src/tunnel.ts.

I executed the generated remote runner in a real POSIX shell with an isolated temporary HOME, uname returning Darwin/x86_64, and a curl stub that reports a download attempt. The unmodified runner reaches the downloader. This is a simulated remote platform on Windows with Git Bash, not a native Intel Mac or a live SSH connection.

The current release assets were checked using gh release view --repo pingdotgg/t3code --json tagName,assets.

Expected behavior

Explain that darwin-x64 has no T3 release archive and exit before downloading. Supported Darwin/arm64 and Linux/x86_64/aarch64 hosts should continue to the downloader.

Scope

Only automatic SSH archive installation. This does not request Intel macOS support or change explicitly configured Node script runners.