publish arm64 agent images: registry only has linux/amd64 manifests

[elronbandel]

Summary

Published agent images at ghcr.io/exgentic/agents/* only have linux/amd64 manifests. After #189 made the fleet multi-arch and #199 removes platform forcing, replay tests fail on arm64:

ghcr.io/exgentic/agents/codex:latest: no match for platform in manifest: not found

The replay test's bake path intentionally uses published agent images (black-box CLI test). Until arm64 manifests are published, replay tests cannot run natively on arm64.

Fix

Rebuild and push agent images with linux/arm64 manifests alongside linux/amd64. The bake-plan.sh script already emits platforms: ["linux/amd64","linux/arm64"] for agents (fixed in #199), so a re-publish via the release CI should produce the multi-arch manifests.

Related

• Fleet release: publish the 5-agent combo fleet + base-image CVE fixes #189 — fleet base images went multi-arch
• fix: remove linux/amd64 platform forcing — fleet is multi-arch after #189 #199 — removes platform forcing; exposes this gap on arm64