[scotwells]

When an activity policy fails, customers can see gaps in their resource timelines. Route those failures to the team that owns the policy so the right team can investigate and restore missing activity entries, including events already queued for retry.

Set ownership on the ActivityPolicy resource's metadata.labels, for example:

metadata:
  labels:
    meta.datumapis.com/service: network-services
    meta.datumapis.com/team: delivery

meta.datumapis.com/service becomes the alert's service label; meta.datumapis.com/team becomes its team label. Existing Alertmanager routes send service=network-services to Deliver; team=delivery records the policy's owning team. Setting the team label alone does not create a route.

Policies without an owner still alert: a missing service stays unset, a missing team falls back to sre, and missing ownership metrics do not suppress failures. Ownership changes also apply to existing retry failures.

Validated processor tests and ten alert-rule scenarios covering ownership changes, missing metadata, replicas, cluster isolation, and scrape-label collisions; CI is green.

Roll out with https://github.com/datum-cloud/infra/pull/6325 and the policy labels in datum-cloud/network-services-operator#515 and datum-cloud/dns-operator#192. Include this change in staging's federated-events branch before deployment.

Related to https://github.com/datum-cloud/infra/issues/6019.