refactor: route named-type lookup through resolver

[ktjn]

Summary

• route shared named-type and enum resolution through the common declaration resolver
• preserve semantic-only and enum-projection behavior, exact versions, and emitter output

Validation

• focused emitter and golden tests: 113 passed
• full suite serially: 3155 passed, 67 skipped
• ruff format/check and mypy baseline ratchet passed

Reviewed by subagent: no findings.