Introduce a commercial license option alongside AGPL-3.0-only, require a
CLA for contributors, and document the terms in COMMERCIAL.md and
NOTICE. Add a script to stamp SPDX headers on Go files and apply it
across the tree.
Register FedWiki and Stripe providers at boot, persist provider
operations, and stamp owned resource keys.
Rename the FedWiki entitlement key from `sites` to `fedwiki_sites`
and drive the operator integration nav from provisioning providers.
cgalo5758