[WIP] Fix invalid field 'host=x86' in CMake configuration

[Copilot]

• Understand the issue: VS 2017 (majorVersion 15) with bundled CMake 3.12.18081601-MSVC_2 fails when host=x86 toolset is passed via -T flag
• Identify root cause: kit.ts line 809 sets toolset: majorVersion < 15 ? undefined : host, meaning VS 2017 gets host=x86 which its bundled CMake doesn't support
• Research related issues: Failed to generate projects for older Visual Studio #1352 (VS 2010 fix), contains invalid field 'host=amd64'. #2790 (host=amd64 fix)
• Implement fix: Change threshold from majorVersion < 15 to majorVersion < 16 to exclude VS 2017 from host= toolset generation
• Update related Clang for MSVC kit generation similarly
• Add unit test for the fix
• Add changelog entry
• Run code review and security scan

Original prompt

---

This section details on the original issue you should resolve

<issue_title>that contains invalid field 'host=x86'.</issue_title>
<issue_description>### Brief Issue Summary

When selecting Visual Studio Enterprise 2017 Release - x86 configuring cmake fails.
Selecting Visual Studio Professional 2022 Release - x86 works.

CMake Tools Diagnostics

{
  "os": "win32",
  "vscodeVersion": "1.83.1",
  "cmtVersion": "1.19.51",
  "configurations": [
    {
      "folder": "c:\\work\\sdp\\slc_env_agent_ex",
      "cmakeVersion": "3.12.18081601",
      "configured": true,
      "generator": "Visual Studio 15 2017",
      "usesPresets": false,
      "compilers": {}
    }
  ],
  "cpptoolsIntegration": {
    "isReady": false,
    "hasCodeModel": false,
    "activeBuildType": "",
    "buildTypesSeen": [],
    "requests": [],
    "responses": [],
    "partialMatches": [],
    "targetCount": 0,
    "executablesCount": 0,
    "librariesCount": 0,
    "targets": []
  },
  "settings": [
    {
      "communicationMode": "automatic",
      "useCMakePresets": "auto",
      "configureOnOpen": true
    }
  ]
}

and here is the output when running the CMake:configure command:
[driver] Switching to kit: Visual Studio Enterprise 2017 Release - x86
[main] Configuring project: slc_env_agent_ex 
[cmake] Selecting Windows SDK version 10.0.22621.0 to target Windows 10.0.19045.
[cmake] CMake Error at CMakeLists.txt:3 (project):
[cmake]   Generator
[cmake] 
[cmake]     Visual Studio 15 2017
[cmake] 
[cmake]   given toolset specification
[cmake] 
[cmake]     host=x86
[cmake] 
[cmake]   that contains invalid field 'host=x86'.
[cmake] 
[cmake] 
[cmake] Configuring incomplete, errors occurred!
[cmake] See also "c:/work/sdp/slc_env_agent_ex/build/CMakeFiles/CMakeOutput.log".
[cms-driver] Error during CMake configure: 
	Error: Configuration failed.
	at CMakeServerClient.onMessage (c:\Users\Administrator\.vscode\extensions\ms-vscode.cmake-tools-1.19.51\dist\main.js:97258:33)
	at CMakeServerClient.onMoreData (c:\Users\Administrator\.vscode\extensions\ms-vscode.cmake-tools-1.19.51\dist\main.js:97231:18)
	at Socket.emit (node:events:513:28)
	at addChunk (node:internal/streams/readable:324:12)
	at readableAddChunk (node:internal/streams/readable:297:9)
	at Readable.push (node:internal/streams/readable:234:10)
	at Pipe.onStreamRead (node:internal/stream_base_commons:190:23)

Debug Log

[main] Configuring project: slc_env_agent_ex 
[main] Saving open files before configure/build
[cms-driver] Run doRefreshExpansions
[expand] expanded ${workspaceFolder}/build
[driver] Start configure 
[driver] Running pre-configure checks and steps
[cms-driver] Run doRefreshExpansions
[expand] expanded ${workspaceFolder}/build
[cmake] Selecting Windows SDK version 10.0.22621.0 to target Windows 10.0.19045.
[cmake] CMake Error at CMakeLists.txt:3 (project):
[cmake]   Generator
[cmake] 
[cmake]     Visual Studio 15 2017
[cmake] 
[cmake]   given toolset specification
[cmake] 
[cmake]     host=x86
[cmake] 
[cmake]   that contains invalid field 'host=x86'.
[cmake] 
[cmake] 
[cmake] Configuring incomplete, errors occurred!
[cmake] See also "c:/work/sdp/slc_env_agent_ex/build/CMakeFiles/CMakeOutput.log".
[cms-driver] Error during CMake configure: 
	Error: Configuration failed.
	at CMakeServerClient.onMessage (c:\Users\Administrator\.vscode\extensions\ms-vscode.cmake-tools-1.19.51\dist\main.js:97258:33)
	at CMakeServerClient.onMoreData (c:\Users\Administrator\.vscode\extensions\ms-vscode.cmake-tools-1.19.51\dist\main.js:97231:18)
	at Socket.emit (node:events:513:28)
	at addChunk (node:internal/streams/readable:324:12)
	at readableAddChunk (node:internal/streams/readable:297:9)
	at Readable.push (node:internal/streams/readable:234:10)
	at Pipe.onStreamRead (node:internal/stream_base_commons:190:23)
[visual-studio] OK running C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\VC\Auxiliary\Build\vcvarsall.bat x86 , env vars: {"DevEnvDir":"C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Enterprise\\Common7\\IDE\\","Framework40Version":"v4.0","FrameworkDir":"C:\\WINDOWS\\Microsoft.NET\\Framework\\","FrameworkDIR32":"C:\\WINDOWS\\Microsoft.NET\\Framework\\","FrameworkVersion":"v4.0.30319","FrameworkVersion32":"v4.0.30319","INCLUDE":"C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Enterprise\\VC\\Tools\\MSVC\\14.16.27023\\ATLMFC\\include;C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Enterprise\\VC\\Tools\\MSVC\\14.16.27023\\include;C:\\Program Files (x86)\\Windows Kits\\NETFXSDK\\4.6.1\\include\\um;C:\\Program Files (x86)\\Windows Kits\\10\\include\\10.0.22621.0\\ucrt;C:\\Program Files (x86)\\Windows Kits\\10\\include\\10.0.22621.0\\shared;C:\\Program Files (x86)\\Windows Kits\\10\\include\\10.0.22621.0\\um;C:\\Program Files (x86)\\Windows Kits\\10\\include\\10.0.22621.0\\winrt;C:\\Program Files (x86)\\Windows Kits\\...

</details>



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- Fixes microsoft/vscode-cmake-tools#4051

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