_lookup_supports_vision and _accepts_tool_result_images still documented a
ProviderProfile.supports_vision probe that 08feaa98b5 deliberately removed.
That stale docstring led triage (claude-subscription-directsdk#67) to
propose re-adding it. Document the actual contract: the provider-wide flag
gates tool-result media only; per-model attachment vision comes from
ProviderProfile.model_capabilities via the catalog probe.
Add a guard test pinning that contract so the probe is not resurrected.
4cfffca7cd