Validate every live route in probabilistic rollouts

When a service can route individual requests to an experimental provider, a health check for the configured default does not certify the request's eventual path. Treat every route eligible for live traffic as a separate readiness dependency: exercise its authenticated startup contract, record the selected provider per request, and isolate failures by that selection. A passing default path can coexist with immediate failures in the routed cohort. If the experiment is outside the intended feature scope, remove its selection path rather than relying on one local percentage setting. Startup checks still do not prove a complete user interaction.

Applies when: An active canary chooses a provider separately for each request. Keywords: canary routing readiness health provider selection startup speech connection