[documentation] Wrong and breaking info for adding Windows PATH for CLI and pio functionality

Issue on your documentation page for installing shell commands:

• https://docs.platformio.org/en/latest/core/installation/shell-commands.html#piocore-install-shell-commands

There you say:

You need to edit the system environment variable called Path and append C:\Users\UserName\.platformio\penv\Scripts\ path in the beginning of a list...

The content of that location is:

.\penv\Scripts\
├── __pycache__
│   ├── bottle.cpython-311.pyc
│   └── readelf.cpython-311.pyc
├── Activate.ps1
├── activate
├── activate.bat
├── async-json-rpc-server.exe
├── bottle.exe
├── bottle.py
├── deactivate.bat
├── normalizer.exe
├── pio.exe
├── piodebuggdb.exe
├── pip.exe
├── pip3.11.exe
├── pip3.exe
├── platformio.exe
├── pyserial-miniterm.exe
├── pyserial-ports.exe
├── python.exe
├── pythonw.exe
├── readelf.py
├── tabulate.exe
└── uvicorn.exe

There are 3 serious issues with this PATH:

1. You are adding to Windows SYSTEM PATH and not USER PATH, which may break all sort of already installed tools and programs, including Python interpreter.

2. You are telling user to put the PATH addition on the top of the path list, (again) overriding all other PATHs.

3. There are only 3 programs needed, so why are you asking user to add entire directory?
   That include an outdated Python interpreter, and several unknown executables!?

NOTE:
platformio.exe and pio.exe are the same file.

Start with the shell-commands section at docs.platformio.org/en/latest/core/installation/shell-commands.html#piocore-install-shell-commands. Review the Windows PATH guidance against the reported USER versus SYSTEM scope, ordering, and listed executables. Done means the page gives accurate, non-breaking instructions and identifies only the commands users need.