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Reproducible example

pixi info output:

╰─ pixi info
System
------------
       Pixi version: 0.60.0
           Platform: win-64
   Virtual packages: __win=10.0.19044=0
                   : __cuda=12.7=0
                   : __archspec=1=haswell
          Cache dir: D:\pixi\rattler
       Auth storage: D:\pixi\.rattler\credentials.json
   Config locations: No config files found

Global
------------
            Bin dir: D:\pixi\bin
    Environment dir: D:\pixi\envs
       Manifest dir: D:\pixi\manifests\pixi-global.toml

Issue description

I'm trying to put all files created by pixi to E:\pixi, rather than C:\Users\user..., which is wasting the C driver space, while other driver has more space for files.

used these enviroment variables:

PIXI_HOME=D:\pixi
PIXI_CACHE_DIR=D:\pixi\rattler
RATTLER_AUTH_FILE=D:\pixi\.rattler\credentials.json

However:
the RATTLER_AUTH_FILE is not documented at https://pixi.sh/latest/reference/environment_variables/
and
in this page, https://pixi.sh/latest/switching_from/conda/#global-environments

This doesn't allow you to activate the environments using pixi shell -n but it will make the installation of the environments go to the same folder.

the pixi shell -n actually is a wrong command, not exists.

By the way, can make an envirment variable to set a directory that simply could put all pixi files? the PIXI_HOME currently seems it's not a PIXI_HOME actually

Expected behavior

1. RATTLER_AUTH_FILE added in document page https://pixi.sh/latest/reference/environment_variables/
2. fix wrong command pixi shell -n within https://pixi.sh/latest/switching_from/conda/#global-environments
3. make PIXI_CACHE_DIR and RATTLER_AUTH_FILE and others default under PIXI_HOME if it's not set