feat: Implement SoroSusu protocol with 3 key enhancements

[Xhristin3]

TASK 1 - Gas Bounty Incentive (Optimization, Economics, UX):

• Add permissionless finalize_round function with gas bounty reward
• Caller receives 0.1% of platform fee as incentive for decentralized maintenance
• Ensures rounds progress autonomously without backend intervention
• Platform fee: 0.5%, Gas bounty: 10 basis points of fee

TASK 2 - Clawback Deficit Resolution (Finance, Security, Compliance):

• Implement deficit detection when regulated assets are clawed back
• Automatic Safety Pause activation when contract balance < pot
• Recovery surcharge mechanism: 5% split among remaining members
• Democratic voting system: Members vote to skip payout (66% threshold)
• 3-day voting period with deficit tracking
• Prevents entire group from losing savings due to external intervention

TASK 3 - Inter-Contract Priority Scoring (Reputation, Interop, Growth):

• Add reliability_score tracking for members (0-1000 scale)
• Grant-Stream integration: Score > 900 qualifies for fast-track priority
• Inter-contract query functions for ecosystem synergy
• Rewards disciplined savers with easier access to development capital
• Unified financial identity across SocialFi suite

New Contract: contracts/sorususu/

• Complete SoroSusu rotating savings implementation
• Member registration with contribution tracking
• Round management with status tracking
• Comprehensive test suite covering all scenarios
• Workspace integration added to Cargo.toml

Labels: optimization, economics, ux, finance, security, compliance, reputation, interop, growth

closes #210
closes #211
closes #212