Re-home organization overview Artifact Registry entry point to EE

What does this MR do and why?

Implements Step 1 of the monolith/S01 plan (Vue app shell and composition surfaces): re-homes the pre-existing FOSS Artifact Registry (AR) organization overview entry point into ee/, so the AR surface is EE-only ahead of the S01 feature steps.

• The FOSS organizations/show overview no longer renders the "Go to Artifact Registry" link, the two AR-specific empty-state copy variants, the canReadArtifactRegistry mount data, or the can_read_artifact_registry helper key, and no longer imports the generated artifactRegistryOrganizationIndexPath route helper. It exposes CE #description / #actions slots for EE to fill.
• EE restores the entry point unchanged via an override component that fills those slots, an EE organization_show_app_data helper override that re-adds can_read_artifact_registry, and an ee_else_ce bootstrap swap so only the EE build reads the ability and mounts the EE component (the FOSS build stays free of AR frontend code).

Notes

• Feature flag: none in this step (the shared artifact_registry_ui flag lands in Step 3). The whole organization UI is behind ui_for_organizations.
• Changelog: intentionally omitted - the organization UI is dark behind ui_for_organizations (type: wip, default_enabled: false); a changelog entry lands when that UI goes GA.
• i18n: the five Organization|… strings are byte-identical, split between the CE component (settings / default descriptions) and the EE override (the two AR descriptions + "Go to Artifact Registry").

Steps to verify

FOSS	EE (Org admin)	EE(Org user)
		Text should change as org user

1. Enable ui_for_organizations feature flag
2. Visit http://gdk.test:3000/o/default/-/overview in FOSS_ONLY mode and confirm that link to Artifact registry does not exist.
3. Visit http://gdk.test:3000/o/default/-/overview in EE and confirm that link to Artifact registry` does exist.

Related to #604731 (closed)