feat: add federated events exporter

[savme]

The event exporter now resolves its own cell identity: plane type, cluster, and region from config, city resolved in the background from the cluster's ServingLocation. This identity information is used to stamp each event's source

On edge deployments, it also recovers per-event tenant scope from the label Karmada already puts on the event's namespace, instead of a fixed scope for the whole deployment. Management-plane behavior is unchanged.

Note: this bumps k8s dependencies to v0.36, which is required to bring in the locations dependency.

Test plan

• go test
• task generate:openapi, task generate:rbac re-run

Related to datum-cloud/compute#100
Depends on #245

Stack:

• fix: shared processor event extractors #239
• feat: add federated events schema #240
• feat: add federated event Source/Resource/Origin support #245
• feat: add federated events exporter #246 👈
• feat: qualify dedup IDs and bound the exporter queue #248
• feat: federated events transport #250