$validate operation returns 200 OK when it should return a 500 Server Error

[lmsurpre]

Describe the bug
When you invoke $validate at the resource-type level (not the instance level) and an unexpected server error occurs, the current implementation returns a 200 OK with an OperationOutcome description like "An error occurred during validation".

Environment
main

To Reproduce
Steps to reproduce the behavior:

1. register a profile with known bad FHIRPath or something similar to force the server to throw during validation (instead of returning an issue list)
2. invoke $validate at the resource type level

Note the generic error message and the fact that we are missing the exception info in the logs.

Expected behavior
per http://hl7.org/fhir/operation-resource-validate.html

This operation returns a 200 OK whether or not the resource is valid. A 4xx or 5xx error means that the validation itself could not be performed, and it is unknown whether the resource is valid or not.

I think this should be a 5xx.
However, it will be good to confirm that the failure to parse the incoming resource continues to fail with either a 200 OK (with OperationOutcome indicating the failure) or with a 4xx response code.

Additional context

[PrasannaHegde1]

tried $validate operation at the resource type level with below request having us-core-patient profile which does not have one of the required fields 'Patient.gender'.
Request: POST /fhir-server/api/v4/Patient
Requesy body :

{
  "resourceType": "Patient",
    "meta": {
        "tag": [{
            "system": "http://example.com",
            "code": "text",
            "display": "Text"
        }],
        "profile": ["http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient"]
    },
  "language": "en",
    "text": {
        "status": "empty",
        "div": "<div xmlns=\"http://www.w3.org/1999/xhtml\">David(123)</div>"
    },
  "identifier": [{
    "use": "usual",
        "system": "https://example.com",
        "value": "1234"
  }],
    "name": [{
        "given": ["David"]
    }],
    
  "active": true
}

Response : 200 OK.

{
    "resourceType": "OperationOutcome",
    "id": "Error",
    "text": {
        "status": "additional",
        "div": "<div xmlns=\"http://www.w3.org/1999/xhtml\"><p>ERROR</p></div>"
    },
    "issue": [
        {
            "severity": "error",
            "code": "invariant",
            "details": {
                "text": "generated-us-core-patient-4: Constraint violation: gender.exists()"
            },
            "diagnostics": "Caused by: [[expression: gender.exists(), result: false, location: Patient]]",
            "expression": [
                "Patient"
            ]
        }
    ]
}

This is working as expected.