feat: positive-marker repo detection and scaffold auto-registration

[TMHSDigital]

Summary

Hardens and completes the tool-scaffolding subsystem so a repo cannot be born wrong, born unknown, or born unregistered.

• Positive-marker type detection. _detect_repo_type now keys on positive manifest markers (.cursor-plugin/plugin.json => cursor-plugin; package.json => mcp-server) instead of incidental directory presence. An mcp-server rendered with skills/ previously flipped to unknown and silently lost required-workflow enforcement; it now classifies correctly. package.json added to SPARSE_PATHS so mode: all detection sees the marker.
• Registry auto-registration. create-tool.py registers every generated repo in registry.json by default and regenerates derived artifacts via the shared sync_all code path. --no-register is the escape hatch. The live registry is untouched by this PR; registration is exercised hermetically against a temp registry root in tests.
• Callable library entrypoint. Canonical generation logic factored into importable scaffold/generator.py (generate_repo / build_registry_entry / register_in_registry); create-tool.py is now a thin CLI. A second generator can delegate instead of reimplement.
• Convergence contract. standards/born-green-contract.md codifies the born-green acceptance criterion (C1-C6) any generator must satisfy.
• Tests. Born-green test extended with the previously-breaking shapes (mcp-server with skills, empty cursor-plugin) and a registration round-trip.

Bumps VERSION 1.16.3 -> 1.17.0.

Test plan

• pytest -q (238 passed, 1 skipped network-integration)
• python scripts/sync_from_registry.py --check clean (registry untouched)
• py_compile create-tool.py, generator.py, sync_from_registry.py
• mcp-server-with-skills detects mcp-server; empty cursor-plugin detects cursor-plugin
• registration round-trip: schema-valid entry, sync --check clean against temp root
• CI green across Validate, Drift check, Sync, CodeQL, Pages

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

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