unplan: canopy-cr-materialisation done

Ships across three PRs (#82 + #83 + #84). Two conscious deviations from
the plan:

- Step 4: snapshot-list runs on both paths (not skipped on canopy) so
  canopy replicas also get real PVC + kopia-cache sizing from the
  snapshot metadata. Result-picking is by canopyDesiredSnapshotId on
  the canopy path.
- Step 8: canopy RestoreVerification uses a direct hook
  (controllers::canopy::verification::report) rather than a
  NotificationConfig variant. No retry pipeline. Rationale: canopy
  reporting is coupled to spec.canopy_source, not user-configurable,
  and doesn't semantically belong alongside webhook / graphQL.

Deferred follow-ups (out of scope per plan):
- stub-canopy server + wire canopy_integration test into CI
- ops handoff snippet: canopy declarations -> pgro CRs mapping

Author: passcod