[NETSDKE2E] [Dotnetup] Uninstall didn't put PATH / env back to how it was when no dotnetup installs remained

**Install Steps**

Clean machine: Win11 x64 25h2 ENU
Install dotnetup tool: iwr https://aka.ms/dotnetup/get-dotnetup.ps1 | iex

**Repro Steps**
1. Add dotnetup to the PATH in Current session.
2. Install the latest stable .NET SDK (10.0.301) using following step:
`dotnetup > choose 'Yes, proceed with default and install' `
3. Uninstall the latest stable .NET SDK (10.0.301) using following command:
`dotnetup sdk uninstall latest`
4. Check the PATH / env.

**Actual Result**
Uninstall didn't put PATH / env back to how it was. The '**dotnet**' folder didn't be removed under 'C:\Users\shiha\AppData\Local'.

**Expected**
Uninstall should put PATH / env back to how it was. The 'dotnet' folder should be removed under 'C:\Users\shiha\AppData\Local'.

Reproduce the issue on Win11 using the get-dotnetup.ps1 install entry point, then trace the `dotnetup sdk uninstall latest` flow while checking PATH, environment variables, and the local `dotnet` folder. Done means uninstall restores the prior PATH and environment state and removes the folder when no dotnetup installs remain.

Written by the indexing model from the issue text.