Allow protocol token and governor extension

[dangerousfood]

Summary

• mark DeepstateToken.mint virtual so proposal repositories can add issuance policy while retaining the audited token base
• mark DeepstateGovernor.proposalThreshold and quorum virtual so proposal repositories can specialize supply accounting while retaining the audited Governor base
• keep every DGP-003-specific contract, interface, test, and deployment artifact in dangerousfood/dgp-003

DGP-003 integration

The DGP-003 repository pins this branch and owns all seven contracts deployed by or used in DGP-003. This PR contains only the minimal reusable extension points required by those inherited contracts.

Verification

• full deepstate-protocol suite: 146 passing
• DGP-003 suite: 85 passing
• DGP-003 production contracts: 100% line, statement, branch, and function coverage
• complete 30-action proposal lifecycle passes against current Robinhood mainnet state on a fork

[dangerousfood]

DGP-003 now vendors its modified token, Governor, and Rewarder extension bases directly in dangerousfood/dgp-003. The DGP-003 submodule is pinned back to upstream master, so this protocol PR is no longer required.