Add Makefile target to upgrade OLMv0 install to OLMv1 install

Overview

Add a make target (e.g., make upgrade-v0-to-olmv1) that automates upgrading an existing OADP operator installation managed by OLMv0 (Subscription/OperatorGroup) to be managed by OLMv1 (ClusterExtension).

Background

PR #2160 introduces OLMv1 lifecycle Makefile targets (test-olmv1, test-olmv1-cleanup) for fresh OLMv1 installs. However, there is no automation for the migration/upgrade scenario where an operator is already installed via OLMv0 and needs to be transitioned to OLMv1 management.

Goals

• Add a parameterized Makefile target (e.g., make upgrade-v0-to-olmv1) that:
  1. Detects/removes the existing OLMv0 Subscription and OperatorGroup for OADP.
  2. Creates the necessary ServiceAccount and RBAC (ClusterRoleBinding) for the OLMv1 installer.
  3. Creates a ClusterExtension pointing to the desired package/channel/version.
  4. Waits for the ClusterExtension to reach Installed=True.
• Reuse existing OLMV1_* Makefile variables (package, namespace, channel, version, catalog, catalog-image, service-account) introduced in PR #2160 for consistency.
• Handle inline.watchNamespace (OLMv1) vs. watchNamespace env var / OperatorGroup scope (OLMv0) differences.

References

• PR #2160: https://github.com/openshift/oadp-operator/pull/2160
• Related issue #2193 (test coverage for OLMv0→OLMv1 migration): https://github.com/openshift/oadp-operator/issues/2193
• OLMv0 install mode in CSV: https://github.com/openshift/oadp-operator/blob/7e53a850ffc68b183e6fd7dd3cc134170b8b7f76/config/manifests/bases/oadp-operator.clusterserviceversion.yaml#L467-L475
• OLMv0 watchNamespace config: https://github.com/openshift/oadp-operator/blob/7e53a850ffc68b183e6fd7dd3cc134170b8b7f76/config/manager/manager.yaml#L63-L66

Requested by @kaovilai on PR #2160 comment: https://github.com/openshift/oadp-operator/pull/2160