fix(deploy): restore Komodo image auto updates

[djkcyl]

Summary

• replace the interpolated application image tag with concrete stable and beta Compose definitions so Komodo can detect registry digest changes
• update the Komodo channel-switching and proxy deployment documentation
• cover both release channels in the release configuration tests

Verification

• pnpm test
• production Global Auto Update created a successful service-scoped Auto Redeploy for server and caddy
• production is healthy on v0.15.0-beta.3; Redis and voice services were not recreated