[codex] Tolerate Local Knowledge embedding fingerprint drift

[oscharko]

What changed

• Treat embedding-space fingerprint drift as a warning instead of a structural embedding identity incompatibility.
• Keep hard failures for provider, model, dimensions, metric, normalization, instruction version, and dimensions-param changes.
• Project cross-pod fingerprint mismatches as unknown with reindex guidance rather than incompatible.
• Refresh compatible endpoint-bound capsule embedding identities before normal Local Knowledge indexing so new vectors are written with the current verified identity.

Root cause

A byte-exact embedding-space fingerprint drift was using the same failure path as true embedding identity changes. That caused normal Local Knowledge indexing to fail with LOCAL_KNOWLEDGE_CONFLICT even when the model identity was structurally compatible.

Validation

• npm run typecheck
• npm run lint
• npm run format:check
• npm test (976 files, 16,553 passed, 2 skipped)
• npm run arch:check
• npm run arch:check:negative
• npm run check:retrieval-quality
• npm run check:grounded-retrieval-quality
• npm run check:grounded-faithfulness