Add -ForceDeallocate support to Stop-AzVM

[Copilot]

This updates Stop-AzVM to expose the new -ForceDeallocate stop behavior for VM deallocation scenarios. The change keeps the existing stop/power-off flows intact while making the new option available only where the Compute API supports it.

• Cmdlet surface

  • Added -ForceDeallocate to Stop-AzVM.
  • Scoped the parameter to deallocate paths only.
  • Kept -StayProvisioned / -SkipShutdown on the power-off path, so unsupported combinations are rejected by parameter binding instead of reaching the service.

• Execution flow

  • Wired -ForceDeallocate through the VM deallocate and hibernate calls.
  • Preserved existing -NoWait, -Force, and -Id behavior.
  • Updated the id-based stop path so the new deallocate parameter sets resolve resource group and VM name correctly.

• Docs

  • Updated Stop-AzVM help syntax and parameter reference.
  • Added an example showing force deallocation during stop.
  • Added a Compute changelog entry for the new parameter.

• Scenario coverage

  • Added focused coverage for:
    • -ForceDeallocate on resource-group and id parameter sets
    • -ForceDeallocate combined with -Hibernate
    • rejection of invalid combinations with -StayProvisioned and -SkipShutdown
    • preservation of existing stop syntax

Example:

Stop-AzVM -ResourceGroupName "testRG" -Name "testVM" -ForceDeallocate

Verification Checklist

• Cmdlet implementation updated with the new/changed parameter(s)
• Model class updated to represent the API schema
• Help content regenerated: new parameter appears in the SYNTAX section and in alphabetical order in the PARAMETERS section
• Examples updated to cover the new parameter(s)
• If adding a new command, add it to the help/Az.Compute.md file
• If adding a new command, register it in Az.Compute.psd1 (CmdletsToExport, alphabetical order)
• New scenario tests cover the full matrix: each new parameter exercised alone and in combination (may share a single test), every affected cmdlet, Update merge semantics, removal/disable paths, and negative/edge cases (mutually exclusive params; $null/empty inputs validated per [ValidateNotNullOrEmpty] or other validation attributes)
• Test assertions check concrete sub-properties (type/enum, collection counts and membership, computed fields) and re-read the resource with a follow-up Get-* call to confirm the values persisted
• Every new .ps1 scenario function is wired into the .cs file as a [Fact] check-in test
• ChangeLog.md updated with a concise, user-focused entry under ## Upcoming Release

• Fixes Get-AzureVMAvailableExtension for ARM #1481 - Closed without Solution #1560

[azure-pipelines]

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