RFC: Extend omnigraph upgrade with explicit storage migrations

[azimafroozeh]

What & why

Propose extending omnigraph upgrade with storage-migration handlers, starting with v6 → v7, to preserve graph history and branch ancestry across upgrades. The default is in-place metadata appends with table-data reuse and deferred cleanup; data-moving exceptions require explicit qualification.

Backing issue / RFC

• Is an RFC PR: RFC 0064: Explicit storage upgrades

Checklist

• Change is focused (one logical change)
• Tests added/updated for behavior changes — N/A, RFC only
• Public docs updated if user-facing surface changed — N/A, no runtime change
• Reviewed against docs/dev/invariants.md; publication, recovery, and cleanup qualification remain required before acceptance

Local verification

• python3 scripts/check-docs.py — passed, 137 Markdown files
• git diff --check — passed
• Rust tests and migration experiments — not run; this PR contains no implementation

Notes for reviewers

The RFC specifies automatic handler selection, read-only preflight, restricted handler writes, recovery, and compatibility CI using genuine predecessor binaries. In-place publication, retained-history handling, and cleanup safety still require prototype evidence. The proposed CI gate is not implemented by this PR.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-09T14:05:35.765199Z	7e2c591	PR opened

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