feat: Add Drifted condition to NodePool status

[moko-poi]

Fixes #1785

Description

This PR adds a Drifted status condition to NodePool resources that indicates when any NodeClaims managed by the NodePool have drifted from their desired configuration. This enables external tools like ArgoCD to monitor drift state at the NodePool level for GitOps workflows.

Implementation Details:

• Added DriftedNodeClaim resource type to track drifted NodeClaim counts
• Added ConditionTypeNodeClaimsDrifted constant to NodePool status conditions
• Extended cluster state tracking to count drifted NodeClaims per NodePool
• Updated the counter controller to set the Drifted condition based on drift counts
• Added DRIFTEDNODECLAIMS printer column to kubectl get nodepool output
• The condition is set to True when driftedNodeClaimCount > 0, False otherwise

Use Case:
ArgoCD and other GitOps tools can now check the NodePool's Drifted condition to determine if any managed NodeClaims have configuration drift, without needing to query individual NodeClaim resources.

How was this change tested?

• Added comprehensive unit tests covering multiple scenarios:
  • NodePool with no NodeClaims (condition should be nil)
  • NodePool with NodeClaims that have nil drift condition (should be False)
  • NodePool with all non-drifted NodeClaims (should be False)
  • NodePool with some drifted NodeClaims (should be True)
• All tests pass successfully (4 Passed | 0 Failed)
• Verified CRD generation includes the new condition and printer column

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[k8s-ci-robot]

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This pull-request has been approved by: moko-poi
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[k8s-ci-robot]

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[coveralls]

Pull Request Test Coverage Report for Build 20205840409

Details

• 28 of 28 (100.0%) changed or added relevant lines in 2 files are covered.
• 9 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.02%) to 80.308%

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Files with Coverage Reduction	New Missed Lines	%
pkg/controllers/static/provisioning/controller.go	2	58.54%
pkg/controllers/provisioning/scheduling/preferences.go	7	88.76%

Totals
Change from base Build 19948193551:	-0.02%
Covered Lines:	11888
Relevant Lines:	14803

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💛 - Coveralls

[moko-poi]

@gjtempleton @tallaxes

Hi! I've rebased this PR onto the latest main branch and resolved the conflicts.
Could you please review this PR when you have a chance? Thank you!