Centralize Codex dashboard ownership into CodexDashboardAuthority

Codex history persistence keying with new identifier

Deduplicate Codex identity normalization

Use runtime email for managed Codex refresh guards

Guard Codex refresh results by canonical identity

Reconcile Codex accounts by canonical identity

Preserve auth-backed Codex account identity at runtime

Isolate test state leaks in settings and Codex override stores

Delete codex-current-baseline.md

docs: update appcast for 0.20.0-beta.1

chore: prepare 0.20.0-beta.1 release

Clarify conditions for appending `+ openai-web` in Codex source-label decoration and update characterization coverage documentation to reflect new tests added.

Lock Codex parity baseline

Document stable seams for menu behavior tests

Rewrite flaky codex menu tests