Vue 3 migration: organization Continuous Deployment (CD) SPA

What does this MR do and why?

Adds the vue3_migrate_organizations_cd feature flag and a vue3_migration.yml for the organization Continuous Deployment (CD) SPA entrypoint. It opts into Option 1: the bundler builds a Vue 2 and a Vue 3 chunk, and Rails serves the Vue 3 chunk only when the flag is on (default-off).

One entrypoint, pages/organizations/continuous_deployment/show, mounting the ee/cd app (CdRoot, Apollo) via initSinglePageApplication. status: rollout behind vue3_migrate_organizations_cd.

Risk

Low. The ee/cd tree (37 components + utils) and the shared SPA machinery were audited against the real Vue 2→3 breakers: data() is a function throughout, no removed filters: component option, no Vue.extend/propsData imperative mounts, no Vue.observable/$children/local functional components/custom directive hooks. The mount path already uses new Vue({ el, render }). The SPA renders no GFM/data-reference-type markup, so the shared issuable-popover Vue 3 issue does not apply here. Covered by ee/spec/frontend/cd (green under Vue 3).

References

• Migration issue: Vue 3 migration: organization Continuous Deploy... (#629041)
• Epic: &23285

Screenshots or screen recordings

How to set up and validate locally

1. Enable the flags in the Rails console:

   Feature.enable(:ai_native_deploy)
   Feature.enable(:vue3_migrate_organizations_cd)

2. Visit /o/default/-/deploy. Confirm the console shows [V] Using Vue.js 3 (with @vue/compat) for CdRoot.
3. Navigate across applications / environments and into an application/environment detail; confirm breadcrumbs show resource names and Apollo views load.
4. Run VUE_VERSION=3 yarn jest ee/spec/frontend/cd.

MR acceptance checklist

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