Feature: Add shadcn hinting to the CLI output

[jherr]

Which project does this relate to?

Create Tanstack App

Describe the bug

LLMs get shadcn install commands wrong. https://x.com/shadcn/status/1894806293304721535 Hint the LLM that is running our CLI that it needs to use shadcn instead of shadcn-ui by point it at the docs.

Your Example Website or App

http://jherr.dev

Steps to Reproduce the Bug or Issue

Run pnpx create-tsrouter-app and see the results at the end.

Expected behavior

When shadcn is selected it should have a pointer to the shadcn documentation for LLMs (and humans) to know how to add shadcn components.

Screenshots or Videos

No response

Platform

• OS: all

Additional context

No response