fix: use accumulator in lo.Reduce for disruption pod count

[nicknikolakakis]

Summary

The lo.Reduce callback in Command.LogValues() discards the accumulator (_ int), so the pod-count field in disruption logs only reports the last candidate's pod count instead of the sum across all candidates.

Before: func(_ int, cd *Candidate, _ int) int { return len(cd.reschedulablePods) }
After: func(acc int, cd *Candidate, _ int) int { return acc + len(cd.reschedulablePods) }

Single-candidate disruptions were unaffected (last == only), but multi-node consolidation under-reported.

Fixes #2888

Test plan

• go build ./pkg/controllers/disruption/... — builds clean
• Existing disruption tests (CI)

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