[docs] Issue with `cargo add` Command for Tauri Plugin Installation

Hi,

I encountered a cargo error while trying to install a Tauri plugin in my project following the manual setup guide.

The original command I used was:

cargo add tauri-plugin-autostart --target 'cfg(any(target_os = "macos", windows, target_os = "linux"))'

This resulted in an error. However, when I modified the command to:

cargo add tauri-plugin-autostart --target 'cfg(any(target_os = "macos", target_os = "windows", target_os = "linux"))'

The issue was resolved, and the error disappeared.

It seems there’s a syntax inconsistency causing the problem. Could this be clarified in the documentation to prevent similar issues for other users?

Thank you!

Start with the manual setup guide section that documents installing the Tauri plugin with cargo add. Compare the documented target expression with the working command reported here, then update the example so the Windows target syntax is explicit and verify the guide no longer shows the failing form.