feat: Add detailed logging for consolidation blocking reasons

[moko-poi]

Fixes #2238

Description

Adds detailed structured logging to ValidatePodsDisruptable() to help operators understand why nodes cannot be consolidated.

Previously, Karpenter would loop with generic "marking/removing consolidatable" messages when a node couldn't be consolidated. Now it logs specific details:

• Which pod is blocking consolidation
• The blocking reason (do-not-disrupt annotation or PDB violation)
• Which PDB is preventing eviction
• List of affected pods for PDB violations

Example output:

cannot consolidate node, PDB prevents eviction
  node="ip-10-0-1-100"
  pods=["default/mysql-0"]
  pdb="default/mysql-pdb"
  reason="pdb-blocks-eviction"

How was this change tested?

Verified compilation and existing tests pass. The change only adds logging without modifying behavior.

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

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[coveralls]

Pull Request Test Coverage Report for Build 19798868290

Details

• 23 of 23 (100.0%) changed or added relevant lines in 1 file are covered.
• 13 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.03%) to 80.277%

---

Files with Coverage Reduction	New Missed Lines	%
pkg/controllers/static/provisioning/controller.go	2	58.54%
pkg/controllers/disruption/consolidation.go	4	88.0%
pkg/controllers/provisioning/scheduling/preferences.go	7	88.76%

Totals
Change from base Build 19683853291:	-0.03%
Covered Lines:	11877
Relevant Lines:	14795

---

💛 - Coveralls

[moko-poi]

Hi @mwielgus @tallaxes,
Could you please take a look at this PR when you have a chance?