fix(federation): normalize vector clocks and tighten promotion scoring

[Fail-Safe]

Summary

• Normalize live vector clocks so legacy display-name buckets are pruned from current federation state, event emission, merge, and conflict comparison paths.
• Tighten short-to-mid consolidation scoring so one-source provenance traces do not promote from passive search hits alone.
• Add regression coverage for legacy vector-clock cleanup and one-source promotion scoring.

Root Cause

Older federation state could carry pre-cortex-ID vector-clock buckets keyed by display names. Those buckets were inert but kept propagating through merges and status output. Separately, one-source session-summary-shaped traces could still cross the short-to-mid threshold through passive search-hit activity even though single-source lineage credit was already gated off.

Validation

• go build ./...
• go test ./...
• go vet ./...
• go test -race ./...
• Hermes MCP smoke test: list, create, recall, and search all passed in a test cortex.