Validator consolidation eligibility

[clintjeff2]

Motivation

• Provide large pool operators with an EIP-7251 consolidation scanner that identifies consolidation-eligible validator groups and recommends optimal merges under the 2048-ETH cap.
• Ensure fleet scanning of up to 10,000 validators runs off the main thread using chunked processing to avoid blocking the UI.
• Estimate annual gas savings from merges and surface a readiness score to help prioritize operator action.

Description

• Add core consolidation algorithm and utilities in src/utils/consolidationEligibility.ts that groups validators by withdrawal credentials, bins balances under the 2048-ETH cap, computes readiness scores, and returns sortable recommendations.
• Add ETH math and gas estimation helpers in src/utils/ethMath.ts and src/utils/gasEstimator.ts used by the consolidation logic.
• Implement a chunked web worker scanner at src/workers/consolidationScannerWorker.ts that processes validators in 500-validator chunks and posts progress/complete messages.
• Add the useConsolidationEligibility hook in src/hooks/useConsolidationEligibility.ts to manage the worker lifecycle and state, a ConsolidationDashboard component in src/components/validators/ConsolidationDashboard.tsx, and mount the dashboard in the existing ValidatorDashboard UI.

Testing

• Ran npm run lint which completed successfully (noting one unrelated warning in src/hooks/useNodeList.ts).
• Ran npx tsc --noEmit which completed without type errors.
• Ran npm run build (Next.js production build) which compiled and generated pages successfully.
• Attempted a Playwright screenshot run but it failed because Playwright browser binaries are not installed in the environment (not a code failure).

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Closes #48

[clintjeff2]

@JamesEjembi please review and merge