Make /process/web overwrite behavior configurable instead of always replacing existing collections. Reasoning behind it: When trying to import all URLs of a website using the API, I want them all to end up in the same knowledge base. Currently that was not possible because every new request would replace the knowledge base (collection) instead of just adding the content of the new URL to the collection.

See #21336

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Changelog Entry

Description

Make /process/web overwrite behavior configurable instead of always replacing existing collections. Reasoning behind it: When trying to import all URLs of a website using the API, I want them all to end up in the same knowledge base. Currently that was not possible because every new request would replace the knowledge base (collection) instead of just adding the content of the new URL to the collection.

Changed

• Made POST /api/v1/retrieval/process/web respect a request-body overwrite flag instead of always forcing overwrite.
• Updated frontend retrieval API helper to pass overwrite (default true) so existing behavior remains unchanged unless explicitly set.

Added

• Added OpenAPI/Swagger documentation for the overwrite field on ProcessUrlForm.
• Added backend tests covering default overwrite=true and explicit overwrite=false behavior.

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