Fix v0.7.7 registered-root lookup

[kforris]

Summary

• match historical Project object kinds case-insensitively when loading confirmed registered roots
• cover the production-shaped capitalized kind in the temporary PostgreSQL fixture

Reproduction

The post-deploy 0.7.7 writeback labeled a file inside the confirmed Boron Context root as registered_project_root_unavailable because the query expected lowercase project while the stored ontology kind is Project.

Verification

• npm run check: 69 passed, 13 environment-skipped; held-out metrics unchanged at 1.00 with zero wrong-project retrieval/writeback
• isolated PostgreSQL migrations and integration: 13 passed
• format, typecheck, plugin cache key, npm audit: passed

Boundary

Narrow post-deploy correctness follow-up for the same 0.7.7 milestone; no history rewrite or external fetch.