Implement DriftCore MVP foundations

[rovo79]

Summary

• expose Drupal entity schema and configuration resources plus Drush tools from the MCP server and add smoke/unit coverage
• add SDK generation and sandbox execution flows to the agent runner with associated tests
• provide a Drupal 11 Docker sandbox, CI workflow, repository ignores, and the MVP RFC documentation

Testing

• npm run lint --prefix packages/server
• npm run test --prefix packages/server
• npm run integration --prefix packages/server
• npm run lint --prefix packages/agent-runner
• npm run test --prefix packages/agent-runner
• npm run integration --prefix packages/agent-runner

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Codex Task