Infer Docker registry host from workspace profile

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• auth-docker-infer-region-hosts [Files changed]

---

Changes

Infer the Artifact Registry region for auth docker configure from the workspace metastore, while retaining the deprecated --region override for one release. Add auth docker host --profile <name> to report the registry hostname and whether its credential helper is configured.

Why

Users should not need to discover and manually supply a workspace's home region or reconstruct its registry hostname.

Tests

• ./task checks
• go test ./libs/dockercredentials ./cmd/auth ./cmd/root -count=1
• go test ./acceptance -run '^TestAccept/cmd/auth/docker/help$' -count=1 -timeout=10m

This PR was written by Codex.

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• PR number: 6781
• Commit SHA: d4fef205e276b931713ae3c07a131d34f8940685

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Approval status: pending

/cmd/auth/ - needs approval

6 files changed
Suggested: @simonfaltum
Also eligible: @renaudhartert-db, @hectorcast-db, @parthban-db, @tanmay-db, @Divyansh-db, @tejaskochar-db, @mihaimitrea-db, @chrisst, @rauchy

General files (require maintainer)

6 files changed
Based on git history:

• @pietern -- recent work in cmd/auth/docker/, libs/dockercredentials/, .nextchanges/cli/

_{Any maintainer (@andrewnester, @anton-107, @denik, @pietern, @shreyas-goenka, @simonfaltum, @renaudhartert-db, @janniklasrose, @lennartkats-db, @rugpanov, @rclarey) can approve all areas.
See OWNERS for ownership rules.}