docs: record workspace conflict audit merge

[yha9806]

Summary

• record yha9806/vulca-platform PR Release vulca v0.23.0 #36 and merge commit 3310093131132268ec9658736d3bd172ecccbe58
• update the Workspace production persistence spec, source index, durable-review status, release-readiness gate, M5 closeout, and manifest
• preserve the boundary that PR Release vulca v0.23.0 #36 is compatibility snapshot revision/conflict/audit evidence, not full production authorization, typed aggregates, release-owner audit semantics, operation-specific writes, or multi-instance readiness

Verification

• python3 docs/review-context/gates/validate_review_context.py
• python3 -m pytest tests/test_review_context_vault.py -q
• git diff --check
• git diff --cached | gemini-agent diff-review --stdin