Institution Registry and Access Control

[feyishola]

Location: on-chain/src/contracts/registry/InstitutionRegistry.cairo

📝 Description
This contract manages institutional registrations, authentication, and role-based access controls for certificate issuers and verifiers within the StarkCert ecosystem.

✅ Requirements

Create a new file: InstitutionRegistry.cairo inside contracts/registry/
Implement institution registration with verification requirements
Add functions: register_institution(), verify_institution(), update_institution_status(), get_institution_details()
Implement role-based access control (Admin, Issuer, Verifier, Student)
Add institution reputation and credibility scoring system
Support institutional hierarchies and delegation mechanisms
Implement institution blacklisting and suspension capabilities

✅ Acceptance Criteria

Institution registration process is secure and auditable
Access controls properly restrict unauthorized operations
Institution verification maintains data integrity and authenticity
Role assignments are flexible and granular
Registry integrates seamlessly with certificate issuance system

🛠️ Please Note:
Create a new file: contracts/registry/InstitutionRegistry.cairo
Branch name: feat/institution-registry
Commit message should include: close #