Reverting manual component registration after Vuetify v3 migration

Goal

After upgrading a Vue 3 project from Vuetify v2 to v3, the migration tool removes manual component registration in favor of the vuetify-loader auto‑import plugin. The project contains legacy code that relies on explicit import statements and the global <v-app> wrapper, leading to a failed mount.

Constraints

• The migration guide does not provide a reverse path for re‑enabling manual registration.
• Re‑introducing <v-app> requires a manual wrapper or fallback component that is not automatically generated.
• Other packages may already depend on Vuetify v3 features, so a partial downgrade could break the build.

Unresolved Decision

It is unclear whether the auto‑import plugin can be toggled back to manual mode, or if a custom plugin must be written to support legacy registration patterns.

Questions

1. What configuration changes, if any, allow the vuetify-loader to revert to manual component registration after a v3 migration?
2. Is there an official or community‑supported method to reinstate the <v-app> component in a Vuetify v3 project without rewriting the entire application?
3. How can a project safely preserve legacy theme overrides that rely on static CSS variables when the runtime API replaces them in Vuetify v3?