Install script does not work on Windows

[loic-sharma]

Repro steps

On Windows:

1. Navigate to: https://docs.page/get-started

2. Click Copy Command in the Install section

3. In PowerShell, paste the command, and run it:

   PS > npx @docs.page/cli init
   At line:1 char:5
   + npx @docs.page/cli init
   +     ~~~~~
   The splatting operator '@' cannot be used to reference variables in an expression. '@docs' can be used only as an
   argument to a command. To reference variables in an expression use '$docs'.
       + CategoryInfo          : ParserError: (:) [], ParentContainsErrorRecordException
       + FullyQualifiedErrorId : SplattingNotPermitted
   

Fix

For Windows users, update the install command to add quotes:

- npx @docs.page/cli init
+ npx '@docs.page/cli' init