Doctrine validation skips bundled terminology guard because Toolguide schema rejects references

Observed while running implement/review for #2658 (TF-034).

## Reproduction

1. Run `spec-kitty agent action implement WP01 --agent --mission `.
2. Run the corresponding review action.
3. Capture doctrine validation warnings.
4. Observe `terminology-guard.toolguide.yaml` skipped because its `references` field is rejected as an extra input by the installed Toolguide model.

## Expected

Packaged governance assets and runtime schemas must be version-compatible. A bundled toolguide should validate and load, or installation/upgrade should fail with an actionable compatibility repair rather than silently dropping it.

Reproduce the issue with `spec-kitty agent action implement WP01 --agent --mission ` and the corresponding review action, then inspect how `terminology-guard.toolguide.yaml` is validated against the installed Toolguide model. Done means the bundled toolguide validates and loads, or installation/upgrade reports an actionable compatibility repair instead of silently skipping it.

Written by the indexing model from the issue text.