Fix tanstack documentation import statement

[mkcode]

It's correct in examples/tanstack, but not in the docs:

better-auth/examples/tanstack/src/routes/__root.tsx

Lines 12 to 13 in 799f11d

	import { authClient } from '@/lib/auth-client'
	import { fetchSession, getCookieName } from '@/lib/auth-server-utils'

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[Copilot]

Pull Request Overview

Fixes the import statement for authClient in the TanStack documentation to match the correct import pattern used in the working example code.

• Moves authClient import from server utilities to the client authentication module
• Aligns documentation with the actual implementation in examples/tanstack

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[erquhart]

Thanks for this!