[DOCS] Install on Windows via winget command instead of PS1 install script

Documentation Type

Missing documentation (feature not documented)

Documentation Location

https://github.com/anthropics/claude-code

Section/Topic

Getting Started

Current Documentation

irm https://claude.ai/install.ps1 | iex

What's Wrong or Missing?

Missing winget command.

Suggested Improvement

I suggest that instead of using:
irm https://claude.ai/install.ps1 | iex

it seems simpler to install using winget:
winget install --id Anthropic.ClaudeCode
winget install --id Git.Git -e --source winget

Impact

Low - Minor confusion or inconvenience

Additional Context

_No response_