fix(dataprotection): protect the cluster restore lifecycle

[leon-ape]

Problem

Cluster deletion can race PVC-scoped restore startup and cleanup. The lifecycle needs one continuous protection protocol while preserving resource ownership.

Changes

• add a Cluster restore lifecycle controller that owns only the Cluster protection finalizer
• validate the PVC to workload to Component to Cluster owner chain before restore work starts
• atomically register verified Cluster/Component identity with target PVC protection
• wait for Cluster protection before creating helper or Restore resources
• terminate Cluster restores through their resource owners in Restore, helper, target-finalizer order
• protect and hand off postReady Restore creation without an unprotected cache window
• roll back unused registration and use optimistic locking for concurrent finalizer changes
• keep target PVC deletion neutral and leave Component deletion out of scope

The implementation exposes Cluster-scoped orchestration only; no nullable Component scope or legacy UID-less adoption is included.

Tests

• Cluster finalizer lifecycle and exact UID filtering
• registration and A-to-B staged upgrade
• startup and postReady protection ordering
• ordered Cluster termination, Retain, missing parent, and foreign resource rejection
• full dataprotection suite, cmd compilation, manifests, and lint

Built on #10844, now merged into main.
Refs #10755.

Split from #10777.

[codecov]

Codecov Report

❌ Patch coverage is 64.96520% with 151 lines in your changes missing coverage. Please review.
✅ Project coverage is 65.91%. Comparing base (63373ca) to head (b839747).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...llers/dataprotection/volumepopulator_controller.go	58.93%	95 Missing and 36 partials ⚠️
...llers/dataprotection/cluster_restore_controller.go	82.14%	13 Missing and 7 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10845      +/-   ##
==========================================
+ Coverage   65.76%   65.91%   +0.14%     
==========================================
  Files         510      511       +1     
  Lines       64958    65414     +456     
==========================================
+ Hits        42721    43117     +396     
- Misses      18449    18491      +42     
- Partials     3788     3806      +18     

Flag	Coverage Δ
unittests	65.91% <64.96%> (+0.14%)	⬆️

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[leon-ape]

/approve