Add external_probe to the licensing feature enumeration, Pro tier
membership, self-hosted feature catalog, feature map, upgrade matrix
and pricing handoff, with the entitlement contract goldens updated.
The capability is served by the community binary - the entitlement
alone gates it, like relay. No existing free functionality changes:
local availability checks stay ungated.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
courtmanr@gmail.com