[Dimank92]

Summary

Closes #201

Reconstructs the zenith-staking crate into a production Soroban contract implementing complete staking, rewards, unbonding, and admin management functionality:

• Core Staking Lifecycle:
  • stake: transfers principal, updates per-staker accruals, distributes carried-over rewards on first stake, enforces emergency pause check.
  • request_unstake: transitions earning stake to cooldown PendingUnstake position with atomic timer restart.
  • withdraw: validates cooldown expiration and transfers principal back to staker.
  • claim_rewards: settles and transfers accrued reward tokens to staker across all active tokens.
  • notify_reward: callable by fee splitter to increase RewardPerToken or carry over rewards when pool is empty.
• Admin Configuration Surface:
  • set_reward_rate & reward_rate: admin-gated rate configuration capped at MAX_REWARD_RATE (10,000 bps) with "reward_rate_set" events.
  • set_cooldown & cooldown: admin-gated unbonding cooldown configuration with "cooldown_set" events; in-flight positions retain original timestamps.
  • set_emergency_unstake, emergency_unstake_enabled, and emergency_unstake: immediate exit bypass during emergency mode, prevents new stakes.
• Contract Build & Spec Alignment:
  • Configured build = "../common/build_meta.rs" and repository.workspace = true in staking/Cargo.toml.
  • Added event-spec test dependency.

Test Verification

All 25 unit, lifecycle, and event spec tests pass cleanly:

test result: ok. 25 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 1.25s

Payout Address

• Wallet: 0xC345C07229307d4f1c7935aD2cAe48e390215808
• Network: Polygon / Base / Arbitrum / Stellar