docs: align the migration prompt with CLI guidance for pnpm dependencies

[naokihaba]

Documentation is

• Missing
• Outdated
• Confusing
• Not sure

Explain in Detail

The migration prompt on the website and the one shown by vp help migrate provide conflicting instructions regarding dependency removal.

The website tells users to remove the old vite, vitest, and @vitest/browser* dependencies after confirming import rewrites. The CLI explicitly tells pnpm users to keep the vite / vitest entries configured by vp migrate.

Since the website prompt also instructs agents to read vp help migrate, following it leads to conflicting instructions.

Verified with Vite+ 0.3.0. This concerns documentation consistency, not a reproduced runtime failure.

Your Suggestion for Changes

Update the website's dependency-removal instruction to include the pnpm exception described in vp help migrate.

Keep the website and CLI migration prompts consistent so users and coding agents receive the same guidance.

❯   vp help migrate
VITE+ - The Unified Toolchain for the Web


Migration Prompt:
  Give this to a coding agent when you want it to drive the migration:

  Migrate this project to Vite+.
  Vite+ replaces the current split tooling around runtime management, package
  management, dev/build/test commands, linting, formatting, and packaging.
  Run `vp help` and `vp help migrate` before making changes.
  Use vp migrate --no-interactive in the workspace root.
  Make sure the project is using Vite 8+ and Vitest 4.1+ before migrating.

  After the migration:
  - Confirm `vite` imports were rewritten to `vite-plus` where needed
  - Confirm `vitest` imports were rewritten to `vite-plus/test` where needed
  - On pnpm, keep the `vite` / `vitest` entries that `vp migrate` aliased to
    the Vite+ packages so the workspace override stays effective; with other
    package managers you can remove them once those rewrites are confirmed
  - Move remaining tool-specific config into the appropriate blocks in
    `vite.config.ts`

  Command mapping:
  - `vp run <script>` is the equivalent of `pnpm run <script>`
  - `vp dev` and `vp test` always run the built-ins; `vp run dev` and
    `vp run test` run the `dev` and `test` scripts from `package.json`
  - `vp install`, `vp add`, and `vp remove` delegate through the package
    manager declared by `packageManager`
  - `vp dev`, `vp build`, `vp preview`, `vp lint`, `vp fmt`, `vp check`,
    and `vp pack` replace the corresponding standalone tools
  - Prefer `vp check` for validation loops

  Finally, verify the migration by running:
  - vp install
  - vp check
  - vp test
  - vp build

  Summarize the migration at the end and report any manual follow-up still
  required.

Documentation: https://viteplus.dev/guide/migrate

Relevant Page

https://viteplus.dev/guide/migrate#migration-prompt

Reproduction (Optional)

No response

Steps to reproduce (Optional)

1. Read the “Migration Prompt” section at https://viteplus.dev/guide/migrate.
2. Run vp help migrate with Vite+ 0.3.0.
3. Compare the dependency-removal instructions under “After the migration”: the website says to remove the old dependencies, while the CLI includes an exception for pnpm.