Support versioning when installing site extensions in AzureAppService…

[rm-dmiri]

…ManageV0 task

Context

Adds support for installing Azure App Service site extensions with explicit version selection, improving flexibility and aligning with user requests for more granular extension management.
📌 Related work item

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Task Name

AzureAppServiceManageV0

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Description

• Adds support for specifying site extensions as name@version (e.g., MyExtension@1.2.3) via the EnableExtensionVersionSupport feature flag.
• If a version is provided (except "latest"), installs that specific version using installSiteExtensionWithVersion.
• If version is "latest", installs the latest available version.
• If no version is provided, installs the extension only if not already present (does not update or reinstall).
• Improves input parsing and error handling for malformed extension strings.
• Updates documentation and unit tests to cover new scenarios.
• No telemetry is emitted; only warnings and debug logs are used.

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Risk Assessment (Low / Medium / High)

Low — Changes are behind a feature flag and maintain backward compatibility.

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Unit Tests Added or Updated (Yes / No)

Yes — Unit tests updated and added for versioned and legacy extension install scenarios.

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Additional Testing Performed

Testing in progress locally.

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Documentation Changes Required (Yes / No)

Yes — Documentation updated to describe the new name@version format and feature flag usage.

Checklist

• Related issue linked (if applicable)
• Task version was bumped — see versioning guide
• Verified the task behaves as expected

[rm-dmiri]

/azp run

[rm-dmiri]

There are changes added to skip installation of site extension in case that "latest" version is specified and site extension is already installed with latest version. This should save some time in task execution for such scenarios.

[rm-dmiri]

/azp run