Inconsistent Search API responses #1391

Hi:

Using the TED Search API I noticed some unexpected behaviours:

Wrongly formatted dates are treated as successful requests

Let the 3rd of March of 2025 be our date of interest on a notice search, for notices published in Denmark.
If our request is place-of-performance=DNK AND publication-date=20250303, with the date formatted as documented, the service does return notices.
However, if our request has the date wrongly formatted, such as place-of-performance=DNK AND publication-date=03032025, the service returns a successful response claiming that no notices were published for the criteria, instead of the expected error code with QueryInvalidFieldFormatDetails as documented in the Swagger UI. This can be tested in the expert search page with these example queries.

Invalid iteration tokens result in a 500 code, which is confusing

A request like

{
 "query": "place-of-performance=DNK",
 "fields": [
 "place-of-performance"
 ],
 "page": 1,
 "limit": 50,
 "scope": "LATEST",
 "checkQuerySyntax": false,
 "paginationMode": "ITERATION",
 "onlyLatestVersions": false,
 "iterationNextToken": "trigger error"
 }

if sent to the API will get as a response a 500 HTTP code. This can be confusing as if a script wrongly modifies the token, the response makes the user believe that the fault is on the API and not on themselves. This last bug was happening a few months ago; maybe it has been solved already but saw no reference to it in the issues.

Thank you for your work!