Fix DDC reconciliation for FDB ConfigMap changes

[Al-assad]

What problem does this PR solve?

Issue Number: N/A

Related PR: N/A

Problem Summary:

A DorisDisaggregatedCluster reads the FoundationDB cluster-file ConfigMap only while reconciling, but the DDC controller does not watch that referenced ConfigMap. When fdb-kubernetes-operator changes the cluster file for a healthy cluster, the MetaService StatefulSet can therefore keep the old FDB_ENDPOINT until another watched resource changes or the controller-runtime cache performs its periodic resync.

This change watches ConfigMap cluster-file create, update, and delete events, maps them to DDCs that reference the ConfigMap, and immediately reconciles those DDCs. Metadata-only ConfigMap updates and DDCs using a direct FDB address are ignored. FDB endpoint resolution now fails before constructing the desired StatefulSet, so a missing or invalid ConfigMap cannot remove the currently deployed FDB_ENDPOINT.

Release note

Changes to an fdb-kubernetes-operator cluster-file ConfigMap now promptly update and roll out the referencing MetaService StatefulSet.

Check List (For Author)

• Test
  • Unit Test
  • Regression test
  • Manual test
  • No need to test or manual test

Test commands:

go test ./pkg/controller -run 'Test(ReorganizeStatusConsidersMetaServiceHealth|MapFDBConfigMapToDDCs|FDBConfigMapPredicate)$' -count=1
go test ./pkg/controller/sub_controller/disaggregated_cluster/metaservice -count=1
go test ./pkg/controller/... -run '^$' -count=1
go vet ./pkg/controller ./pkg/controller/sub_controller/disaggregated_cluster/metaservice

• Behavior changed:

  • No.
  • Yes. Referenced FDB cluster-file changes now trigger DDC reconciliation and MetaService rollout.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label