Remove old staking strategies using SSV clusters

[naddison36]

Summary

Removes the obsolete OETH native-staking and SSV infrastructure following the migration to the vanilla CompoundingStakingStrategy.

Dependency

Requires the governance proposal from [#2971](#2971) to be executed first.

Changes

• Remove the three legacy Native Staking Strategy contracts and proxies
• Remove CompoundingStakingSSVStrategy
• Remove ConsolidationController
• Remove FeeAccumulator and its proxy infrastructure
• Remove the legacy OETH Dripper and Harvester
  • Retain shared harvesting contracts still used by other products
• Remove SSV-specific infrastructure:
  • ISSVNetwork
  • SSV mocks and address constants
  • SSV cluster-management utilities and tasks
  • SSV reward claiming automation
• Port non-duplicative CompoundingStakingSSVStrategy tests to CompoundingStakingStrategy
• Remove obsolete validator registration, removal, consolidation, and harvesting actions
• Retain the Talos actions required to:
  • stake vanilla compounding validators
  • verify deposits and balances
  • request validator withdrawals
  • rebase the OETH Vault
• Remove the P2P validator API integration and configuration
• Remove validator-key encryption and S3 storage utilities
• Remove unused AWS KMS, BLS, UUID, SSV, and P2P dependencies
• Clean up deployment configuration, fixtures, storage layouts, documentation, and OETH diagrams

Context

The old native-staking validators have been consolidated into the new CompoundingStakingStrategy, and the legacy strategies have been removed from the OETH Vault.

The remaining strategy deposits directly into vanilla compounding validators, so the repository no longer needs SSV registration, cluster management, fee accumulators, consolidation controllers, or the old OETH harvesting pipeline.

Verification

• Foundry CompoundingStakingStrategy tests: 116 passed
• Hardhat CompoundingStakingStrategy tests: 9 passed
• forge build --offline
• pnpm prettier:js
• pnpm prettier:ts
• pnpm prettier:sol
• git diff --check