[KTrain5169]

vp migrate warns about rollup, rolldown, or jest dependencies with matching configurations during the first migration to Vite+. The warnings explain manual migration paths to Vite, tsdown, or Vitest.

Detection covers the project root and workspace packages, including shared dependencies declared at the root. It supports common configuration file extensions and the jest field in package.json. Each tool produces at most one warning per run.

Existing Vite+ projects show these warnings only with vp migrate --full. Ordinary vp migrate runs skip them. If no migration is needed, the command displays any requested warnings and exits.

Example output during a first migration or with vp migrate --full. This example has matching dependencies and configurations for all three tools:

! Warnings:
  - Rollup configuration detected. Rollup is API-compatible with Rolldown and can be migrated first before migrating further to tsdown or Vite. Once migrated to tsdown or Vite, re-run vp migrate.
  - Rolldown configuration detected. Rolldown can be migrated to tsdown or Vite, and it is recommended to do so. Once migrated, re-run vp migrate.
  - Jest configuration detected. Vitest is highly compatible with Jest, and so we recommend migrating. See the Vitest Jest migration guide: https://vitest.dev/guide/migration/jest, then re-run vp migrate.

Closes #2546

[fengmk2]

Updated in f9370a6. For existing Vite+ projects, tool migration warning detection now runs only when --full is set.

The Rollup, Rolldown, and Jest migration warnings still appear during the first migration to Vite+. Ordinary vp migrate reruns skip these warnings. vp migrate --full still shows them when matching dependencies and configurations are present.