TSV support @previewVersion

[qiaozha]

If we are encouraging service team to use the @previewVersion and TypeSpec preview version story to avoid the back and forth @added and @removed problem caused by TypeSpec versioning design, we need to make sure TSV will not report errors on the previous preview versions

Output folder 'specification/containerregistry/resource-manager/Microsoft.ContainerRegistry/Registry' appears to contain TypeSpec-generated swagger files, not generated from the current TypeSpec sources. Perhaps you deleted a version from your TypeSpec, but didn't delete the associated swaggers?

specification/containerregistry/resource-manager/Microsoft.ContainerRegistry/Registry/preview/2025-06-01-preview/containerregistry.json

However, we still need to make sure stable apiVersion swaggers are enforced by this check. And the retirement of stable apiVersion requires standard deprecation review process.

[markcowl]

To specify exactly what is needed here:

• Some ARM service teams will need to retain older preview versions in OpenAPI. We will need to remove any violations preventing swagger not generated by tsp compile for preview versions older than the latest version

• ideally this would be true for resource-manager specs, but data-plane checks should still fail for any OpenAPI not generated by tsv.

[mikeharder]

For context, the rule to fail on extra tsp-generated swaggers was added relatively late:

• PR: [TypeSpec Validation] Fail if spec folder contains extra tsp-generated swagger files #33546
• Design: [TypeSpecValidation] Fail if spec folder contains extra tsp-generated swagger files #32861

If we have more information now, and want to tweak the policy, it's fine with me. Just make to understand the reasons for the current policy.

If/when we do change this policy, we may also be able to remove some of the suppressions we needed to add for existing specs, when the rule was added:

azure-rest-api-specs/specification/suppressions.yaml

Lines 4 to 14 in 3fc43b6

	- tool: TypeSpecValidation
	rules: [Compile]
	sub-rules: [ExtraSwagger]
	reason: Extra swaggers left behind when versions were removed from *.tsp files
	paths:
	- ai/data-plane/DocumentIntelligence/preview/2023-10-31-preview/DocumentIntelligence.json
	- ai/data-plane/DocumentIntelligence/preview/2024-02-29-preview/DocumentIntelligence.json
	- ai/data-plane/DocumentIntelligence/preview/2024-07-31-preview/DocumentIntelligence.json
	- ai/data-plane/HealthInsights/preview/2023-03-01-preview/openapi.json
	- ai/data-plane/HealthInsights/preview/2023-09-01-preview/openapi.json
	- azurestackhci/resource-manager/Microsoft.AzureStackHCI/StackHCIVM/preview/2024-07-15-preview/stackhcivm.json