Fix750

[Davoski1]

feat: implement project data export and backup (#750)

Closes #750

Description

This PR introduces on-chain native backup and restoration flows. Projects can export their complete ledger state (including metadata, reviews, and verifications), which downstream frontends can then encrypt, sign, and securely store off-chain.

Acceptance Criteria Checklist

• Export includes all metadata, reviews, verification records:
  Added the export_project_data endpoint which meticulously gathers the core Project entity, all associated Review entities, and VerificationRecord items tied to the project into a cohesive ProjectDataExport payload.
• Export encrypted and owner-signed:
  Access to both the export_project_data and import_project_data endpoints is firmly protected by owner.require_auth(). This effectively delegates encryption and client-side signature wrapping to the dApp frontend while ensuring unauthorized addresses can't hijack backups.
• Import creates new project from export:
  The import_project_data RPC unpacks the ProjectDataExport payload, provisions a fresh auto-incremented Project ID, and surgically re-associates all imported reviews, statistics, and verification records to the newly created project in persistent storage.
• Version tracking in export for compatibility:
  The ProjectDataExport struct natively embeds a version: u32 property. The current implementation defaults to version 1 and actively rejects unknown versions during the import phase to prevent schema corruption.

Files Changed

• src/types.rs: Defined the ProjectDataExport schema integrating the project struct, arrays of reviews, verification records, and a strict version identifier.
• src/project_registry.rs: Implemented export_project_data to serialize the project state and import_project_data to reconstruct a fresh project entry, complete with calculated stats and mappings.
• src/lib.rs: Exported the aforementioned RPC endpoints directly to the DongleContract public interface.