[Az.Compute] Update generation tool version: autorest.powershell v3->v4

[lijinpei2008]

Description

Mandatory Checklist

• Please choose the target release of Azure PowerShell. (⚠️Target release is a different concept from API readiness. Please click below links for details.)

  • General release
  • Public preview
  • Private preview
  • Engineering build
  • No need for a release

• Check this box to confirm: I have read the Submitting Changes section of CONTRIBUTING.md and reviewed the following information:

• SHOULD update ChangeLog.md file(s) appropriately
  • Update src/{{SERVICE}}/{{SERVICE}}/ChangeLog.md.
    • A snippet outlining the change(s) made in the PR should be written under the ## Upcoming Release header in the past tense.
  • Should not change ChangeLog.md if no new release is required, such as fixing test case only.
• SHOULD regenerate markdown help files if there is cmdlet API change. Instruction
• SHOULD have proper test coverage for changes in pull request.
• SHOULD NOT adjust version of module manually in pull request

[azure-client-tools-bot-prd]

Thanks for your contribution! The pull request validation has started. Please revisit this comment for updated status.

[github-actions]

To the author of the pull request,
This PR was labeled "Breaking Change Release" because it contains breaking changes.

• According to our policy, breaking changes can only take place during major release and they must be preannounced.
• Please follow our guide on the detailed steps.
• Required: Please fill in the task below to facilitate our contact,you will receive notifications related to breaking changes.

[Copilot]

Pull Request Overview

This PR updates the autorest PowerShell generation tool from version 3 to version 4 for the Az.Compute module. The update introduces new API patterns, parameter sets, and breaking changes to support the newer autorest.powershell v4 generation framework.

Key changes include:

• Migration from API versioned types to generic interface types in cmdlet signatures
• Addition of new parameter sets with JSON file and string input options
• Introduction of new identity-based parameter sets for better resource management

Reviewed Changes

Copilot reviewed 38 out of 38 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tools/StaticAnalysis/Exceptions/Az.Compute/BreakingChangeIssues.csv	Added 35 new breaking change exceptions for type and parameter changes introduced by autorest v4
Multiple help/*.md files	Updated parameter sets, types, and documentation to reflect new autorest v4 patterns
Multiple docs/*.md files	Updated autorest-generated documentation with new parameter sets and type signatures
src/Compute/Compute.Autorest/generate-info.json	Updated generation ID for new autorest v4 build
src/Compute/Compute.Autorest/README.md	Removed explicit autorest v3 configuration and updated directive patterns
Multiple custom/*.ps1 files	Updated custom cmdlet implementations with new type signatures and parameter sets

[Copilot]

[nitpick] This breaking change from strongly-typed enum to string for the 'Expand' parameter reduces type safety. Consider if this change is necessary or if the enum type can be preserved to maintain compile-time validation.

[Copilot]

[nitpick] The regex pattern uses a negative lookahead which may be difficult to understand and maintain. Consider documenting this pattern or using a more explicit approach to specify which variants should be removed.

[Copilot]

The change from strongly-typed OperatingSystemTypes enum to string reduces type safety and removes IntelliSense support. The PSArgumentCompleter attribute helps but doesn't provide the same compile-time validation as the original enum type.

[dolauli]

Two new parameters added - ConfigFileName, PackageFileName?

[lijinpei2008]

Yes, new parameters have been introduced in the custom file Update-AzGalleryApplicationVersion, and the service team has completed the relevant testing locally.

[lijinpei2008]

I removed this two parameters, because these two parameters were also generated in the previous version, but they were not displayed to users.

[dolauli]

@lijinpei2008 While the changes look good to me, we'll hold on merging until early Nov. At the meantime, could you help authorize a markdown like this for each of the breaking change? We'll need it for publishing migration guides. Just leave a comment in the issue would be fine. Thank you!

## Az.Accounts

### `Get-AzAccessToken`

The default output type is changed from `PSAccessToken` to `PSSecureAccessToken`.That is to change plaintext `PSAccessToken.Token` to `SecureString PSSecureAccessToken.Token`

#### Before
```powershell
$authHeader = @{
    'Content-Type'  = 'application/json'
    'Authorization' = 'Bearer ' + (Get-AccessToken).Token
}
$response = Invoke-RestMethod -Method Get -Headers $authHeader -Uri $uri
```

#### After
```powershell
$secureToken = (Get-AzAccessToken).Token
$ssPtr = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($secureToken)
try {
     $plaintextToken = [System.Runtime.InteropServices.Marshal]::PtrToStringBSTR($ssPtr)
} 
finally {
     [System.Runtime.InteropServices.Marshal]::ZeroFreeBSTR($ssPtr) 
}
$authHeader = @{
    'Content-Type'  = 'application/json'
    'Authorization' = 'Bearer ' + $plaintextToken
}
$response = Invoke-RestMethod -Method Get -Headers $authHeader -Uri $uri
```