Add admin permission callouts for system-wide .NET installations on Windows

[Copilot]

Overview

This PR adds prominent IMPORTANT callouts to inform users that administrative privileges are required when installing .NET system-wide on Windows.

Changes

The article previously only mentioned administrative requirements in the WinGet section as plain text, but this applies to all system-wide installation methods. This PR makes the requirement more visible and consistent across all applicable installation methods.

Sections Updated:

1. Introduction Section - Added IMPORTANT note after the default installation directory explanation to provide early visibility of the administrative privilege requirement

2. Install with Visual Studio Code - Added IMPORTANT note after the first paragraph, since the WinGet configuration file performs system-wide installation

3. .NET Installer - Added IMPORTANT note after the first paragraph, as this method explicitly performs system-wide installations

4. Install with Windows Package Manager (WinGet) - Converted the existing sentence into a proper IMPORTANT note block for better visibility

Format Used:

> [!IMPORTANT]
> If you're installing .NET system-wide, install with administrative privileges.

Sections Excluded:

• Visual Studio - Manages its own copy of .NET, not system-wide
• PowerShell - Explicitly documented as recommended for "nonadmin installs"

The changes ensure users are clearly informed about administrative privilege requirements before attempting system-wide installations, improving the documentation's clarity and reducing potential installation issues.

Fixes #49076

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Callout that admin permissions are required to install system-wide</issue_title>
<issue_description>### Type of issue

Missing information

Description

The article only mentions administrative requirements for the WinGet section, but this applies to the other installation methods.

1. Turn the WinGet section's system-wide paragraph into an important note.
2. For all of the other installation methods (except PowerShell) add this same note after the first paragraph of the H2.

Page URL

https://learn.microsoft.com/en-us/dotnet/core/install/windows

Content source URL

https://github.com/dotnet/docs/blob/main/docs/core/install/windows.md

Document Version Independent Id

d11d0d14-8a03-50e4-5c00-9a4417ad4d0a

Platform Id

6e1e1700-4d16-78f8-02ed-e45abb1f85ae

Article author

@adegeo

Metadata

• ID: 1eeab451-820f-de42-983e-4d0d5764f6ab
• PlatformId: 6e1e1700-4d16-78f8-02ed-e45abb1f85ae
• Service: dotnet-fundamentals
• Sub-service: install

Related Issues</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #49076

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Internal previews

📄 File	🔗 Preview link
docs/core/install/windows.md	docs/core/install/windows

[Copilot]

Pull Request Overview

This PR adds prominent IMPORTANT callouts to inform users that administrative privileges are required when installing .NET system-wide on Windows. The documentation previously only mentioned this requirement as plain text in the WinGet section.

• Added consistent IMPORTANT note blocks across all system-wide installation methods
• Converted existing plain text administrative requirement into proper callout format
• Added AI usage frontmatter to comply with documentation guidelines

[adegeo]

Thanks @meaghanlewis :)