fix(typescript-angular): handle Set in query parameter serialization

[LeovR]

Fixes #23434

When a query parameter is defined with type: array and uniqueItems: true, the typescript-angular generator produces a Set<T> type. However, addToHttpParams only checks Array.isArray(value) to detect collections. Since Array.isArray(new Set()) returns false, the Set falls through to the object-handling branch and query parameters are silently lost.

This adds a value instanceof Set check alongside Array.isArray(value) in the addToHttpParams method of api.base.service.mustache. When a Set is detected, it is converted to an Array before serialization.

cc @TiFu @taxpon @sebastianhaas @kenisteward @Vrolijkx @macjohnny @topce @akehir @petejohansonxo @amakhrov @davidgamero @mkusaka @joscha @dennisameling

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Summary by cubic

Fixes lost query params when uniqueItems: true arrays generate Set<T> in the typescript-angular client by treating Set like arrays in addToHttpParams across form/space/pipe styles. Fixes #23434.

• Bug Fixes
  • In api.base.service.mustache, detect Set alongside arrays and serialize via Array.from(...) for form, space-delimited, and pipe-delimited styles.
  • Extended query-param-form.yaml with a tags query param (array, uniqueItems: true) on explode and non-explode routes.
  • Regenerated typescript-angular samples and updated services to accept tags: Set<string>; added tests for Set-only and combined cases for explode and non-explode.

^{Written for commit ee21602. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 5 files

[macjohnny]

thanks for the fix

[macjohnny]

@LeovR can you please fix the CI failures?

[LeovR]

@macjohnny Should be fixed now.

[macjohnny]

@LeovR can you merge the latest master?

[LeovR]

@macjohnny I rebased onto the current master

[macjohnny]

it seems there are still build failures. can you check them?

[LeovR]

@macjohnny The error should not be related to my change here.
See e.g. https://github.com/OpenAPITools/openapi-generator/actions/runs/23811099934

[macjohnny]

thanks!