pub fn api_key_from_env() -> Result<ApiKey, String>Expand description
Resolve an App Store Connect API key from the environment.
Deliberately per-call rather than at startup: an MCP server that
refuses to start without credentials cannot answer tools/list, which
is the first thing every client asks and the only way a user discovers
what configuration is missing. Unconfigured servers should list their
tools and fail with a useful message when one is called.