docs: fix and update module installation

[selemondev]

This pull request is intended to fix and update the pinia and @pinia/nuxt module installation by fixing the installation commands.

1. fix: The pinia package should be installed as a regular dependency while the @pinia/nuxt module should be installed as a dev dependency.
2. update: I have added pnpm among the package managers to be used when installing pinia and @pinia/nuxt module.

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[posva]

Why the difference? What’s the bug?

[selemondev]

Why the difference? What’s the bug?

Hey @posva . The nuxi CLI, most of the Nuxt modules and the Nuxt devTools install nuxt modules ( including @pinia/nuxt ) as dev dependencies and not as regular dependencies. On the Pinia documentation site, the @pinia/nuxt module is installed as a regular dependency.

[posva]

Thanks. I confirmed with Daniel that this is a thing of the past. Adding it as a dep is fine: https://github.com/nuxt/nuxt/issues/22050