On the first tool call of each session, a background task fires once
and fetches the latest release tag from the GitHub API (5 s timeout).
The result is cached in a static OnceLock for the lifetime of the
process — no repeated network calls.
check_update: returns cached result instantly, or fetches on demand
if the background task hasn't completed yet.
update: downloads the latest tarball for the current platform, extracts
the binary, and atomically replaces the running executable via a
temp-file rename. Requires MCP reconnect to activate new version.
Platform support: macos-aarch64, macos-x86_64, linux-x86_64.
Unsupported platforms return a build-from-source hint.
Tool count: 87 → 89. README and MCP_TOOLS.md updated.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
