Replace System.Management with local CIM

[ml6719]

What changed

• replaces the internal System.Management implementation with a local Microsoft.Management.Infrastructure / CimSession adapter
• narrows the package to the sole consumer shape: net8.0-windows and self-contained win-x64
• retains the existing .NET 8 API, adds deterministic client disposal and classified provider exceptions
• adds provider-shape/job tests, package/publish dependency assertions, third-party notices, and an unchanged self-contained compatibility probe
• provisions 0.6.0-preview.1 package and symbols output

Why

Modern System.Management can load wminet_utils.dll from the machine-installed .NET Framework and fail on older Windows Server installations. The new local CIM path removes that dependency while retaining the Hyper-V root\virtualization\v2 console operations.

Validation

• Release solution build: zero warnings/errors
• 41/41 tests passed
• package and self-contained publish contain no System.Management
• Server 2025 build 26100: elevated and LocalSystem self-contained probes passed
• live VM enumeration, capture, sustained frames, keyboard, mouse, Ctrl+Alt+Del, repeated open/close, async-job start and force-stop passed
• neither System.Management.dll nor wminet_utils.dll loaded

Release gate

This remains draft and the NuGet workflow is deliberately blocked until the unchanged physical-host probe passes on Server 2012 R2, 2016, 2019, 2022, Windows 10, and Windows 11. Server 2016 must include the host with the original failure state.