chore: release v1.23.0-beta.6

[Soju06]

Summary

• Prepares beta release v1.23.0-beta.6 for the 1.23.0 stable train.
• Updates release-managed version files only; release-please remains the stable release owner.
• Merging this PR will publish v1.23.0-beta.6 only after the release-candidate validation checklist below is completed for this exact candidate SHA.
• Synced automatically from release-please PR chore(main): release 1.23.0 #1472; no manual beta workflow dispatch is required.

Changes since v1.23.0-beta.5

• fix(proxy): normalize timestamptz lease expiry in durable lease liveness check (fix(proxy): normalize timestamptz lease expiry in durable lease liveness check #1673) (7913ff9)

Release-candidate validation

Validated candidate: 670ccd4

Complete these checks on the exact candidate SHA above before merging. The beta release guard and publish workflow fail while any item remains unchecked or the SHA is stale.

• Backend/unit/integration gates — CI green at 670ccd4 (unit, integration matrices, migration checks sqlite+postgres)
• Frontend tests/build — CI green at 670ccd4
• Wheel/package validation — CI Package (build) green at 670ccd4
• Docker/container smoke — image built locally from 670ccd4 (sha256:7617fd4c4f8d); booted against a scratch postgres:18-alpine: alembic head 20260806_120000_add_http_bridge_owner_process_epoch, endpoints 200/401, 0 error signatures, AND the beta.5 production regression scenario re-executed in-container (timestamptz-aware lease vs naive clock through lease_is_active) returning correctly instead of raising
• Live upstream/account smoke
• Live upstream/account smoke not required — this beta replaces the hot-patched beta.5 production container with the clean fix(proxy): normalize timestamptz lease expiry in durable lease liveness check #1673 fix; live-path verification continues on the production pool with the rollback runbook staged (no schema delta since beta.5)

Install after publish

uvx --from "codex-lb==1.23.0b6" codex-lb
docker pull ghcr.io/Soju06/codex-lb:1.23.0-beta.6
helm install codex-lb oci://ghcr.io/soju06/charts/codex-lb --version 1.23.0-beta.6 --devel

Promotion

Merge the normal release-please PR to promote this beta-tested train to 1.23.0.