add extension metadata V2 APIs and examples

[jiaqi-beep]

ARM (Control Plane) API Specification Update Pull Request

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Purpose of this PR

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• [ ] New resource provider.
• [x] New API version for an existing resource provider. (If API spec is not defined in TypeSpec, the PR should have been created in adherence to OpenAPI specs PR creation guidance).
• [ ] Update existing version for a new feature. (This is applicable only when you are revising a private preview API version.)
• [ ] Update existing version to fix OpenAPI spec quality issues in S360.
• [ ] Convert existing OpenAPI spec to TypeSpec spec (do not combine this with implementing changes for a new API version).
• [ ] Other, please clarify:
  • edit this with your clarification

Due diligence checklist

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• [x] I confirm this PR is modifying Azure Resource Manager (ARM) related specifications, and not data plane related specifications.
• [x] I have reviewed following Resource Provider guidelines, including ARM resource provider contract and REST guidelines (estimated time: 4 hours).
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Additional information

Viewing API changes

For convenient view of the API changes made by this PR, refer to the URLs provided in the table in the `Generated ApiView` comment added to this PR. You can use ApiView to show API versions diff.

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[openapi-pipeline-app[bot]]

Next Steps to Merge

Next steps that must be taken to merge this PR:

• ❌ This PR is in purview of the ARM review (label: ARMReview). This PR must get ARMSignedOff label from an ARM reviewer.
  This PR is awaiting ARM reviewer feedback (label: WaitForARMFeedback).
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[openapi-pipeline-app[bot]]

Generated ApiView

Language	Package Name	ApiView Link
JavaScript	@azure/arm-hybridcompute	https://apiview.dev/Assemblies/Review/bd79793b6b53409d8de21847c605dc64?revisionId=90c082433c314c489361930e6eb9fc13
Go	sdk/resourcemanager/hybridcompute/armhybridcompute	https://apiview.dev/Assemblies/Review/cc99eb4c91204d199d8e40aed71bc06e?revisionId=219db1285d86440798b7852b94359fea
.Net	Azure.ResourceManager.HybridCompute	There is no API change compared with the previous version
Java	azure-resourcemanager-hybridcompute	https://apiview.dev/Assemblies/Review/b79886348ebe497b9ddc99d286cb6e99?revisionId=3d9b719d7f8b4a36aca969d78d5ff109
Python	azure-mgmt-hybridcompute	https://apiview.dev/Assemblies/Review/4d8650fb76954c6ba3f15e1781007dd9?revisionId=9d0cb2e7e97b40988b35f4291488b83d

[jiaqi-beep]

This change already approved #30656, but we decided to move this to a new preview version

[jiaqi-beep]

previously approved in #30656