Update compatibility message for targeting .NET 10.0 in Visual Studio 18.0

[Copilot]

Updates the .NET SDK compatibility warning to alert users when targeting .NET 10.0 or higher with Visual Studio 2022 17.14 or earlier versions.

Changes Made

Target Update in Microsoft.NET.Sdk.DefaultItems.targets:

• Renamed target from _WarnWhenUsingNET9AndVSPriorTo1712 to _WarnWhenUsingNET10AndVSPriorTo18
• Updated MSBuild version check from 17.12.0 to 18.0.0
• Updated target framework version check from 9.0 to 10.0
• Updated resource name from Net9NotCompatibleWithDev1711 to Net10NotCompatibleWithVS17

New Resource String:

• Added NETSDK1229 message: "Targeting .NET 10.0 or higher in Visual Studio 2022 17.14 is not supported"
• Added new message entry at the end of Strings.resx file following established patterns
• Updated the "latest message added" comment to reference the new message

Localization:

• Automatically generated entries for the new message across all supported localization files (XLF)

Warning Behavior

The warning will now appear when users attempt to build projects with:

• MSBuild version < 18.0.0 AND
• Targeting .NETCoreApp AND
• Target framework version >= 10.0

This follows the same pattern established for previous .NET version compatibility warnings and ensures developers are informed when their tooling may not fully support the target framework version.

Fixes #50748.

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[cremor]

That PR description contradicts itself. At the very top it says "Visual Studio 2022 17.14 or earlier versions." while at the bottom it says "MSBuild version < 17.14.0".

Also, why mention the minor version at all? If VS 2026/MSBuild 18 is required, just say "Targeting .NET 10.0 or higher in Visual Studio 2022 is not supported." (without mentioning any version number).

[marcpopMSFT]

@copilot change Net10NotCompatibleWithVS1713 to Net10NotCompatibleWithVS17, change _WarnWhenUsingNET10AndVSPriorTo1714 to _WarnWhenUsingNET10AndVSPriorTo18 and change the check to be 18.0.0

[Copilot]

@copilot change Net10NotCompatibleWithVS1713 to Net10NotCompatibleWithVS17, change _WarnWhenUsingNET10AndVSPriorTo1714 to _WarnWhenUsingNET10AndVSPriorTo18 and change the check to be 18.0.0

Done! I've updated the code with all the requested changes:

1. Changed Net10NotCompatibleWithVS1713 to Net10NotCompatibleWithVS17
2. Changed _WarnWhenUsingNET10AndVSPriorTo1714 to _WarnWhenUsingNET10AndVSPriorTo18
3. Updated the MSBuild version check from 17.14.0 to 18.0.0

The compatibility warning will now require Visual Studio 18.0 or higher for .NET 10.0 projects. Changes committed in ab74179.

[cremor]

The PR description still contradicts itself. Now the top is wrong and the bottom is correct. And the user facing message was not changed.

[marcpopMSFT]

This change can't go in until we have VS 2026 previews in our hosting images so this'll have to wait for that, likely in GA.