Chained search return an error about multiple resource type, even if only 1 is possible (patient.identifier)

**Describe the bug**
While playing around using this FHIR Server as a backend to a[ XDS Registry](https://github.com/oehf/xds-registry-to-fhir), is was observed that the handling of chained parameters seems cause a unexepcted behavior. Resource "DocumentReference" contain a search parameter "patient" which is already restricted by the spec to the Patient resource. When using a chained search here (e.g. "patient.identifier"), the MS FHIR Server complain about "multiple" possible resource types on this search paramter. Other FHIR Server like Hapi or Firely work as expected.

**FHIR Version?**
R4

**Version used**
Docker image from "mcr.microsoft.com/healthcareapis/r4-fhir-server" (4.0.128)

**Data provider?**
SQL Server

**To Reproduce**
Steps to reproduce the behavior:
1. Trigger a FHIR Query on DocumentReference resource with a chained search parameter, e.g. `/DocumentReference?patient.identifier=urn%3Aoid%3A2.999.1.2.3.4%7CIPF-1714920157063`

**Expected behavior**
SearchResponse is successful and return the expected results.

**Current workaround**
Use a chained search with explicit resource type definition, e.g. "patient:Patient.identifier" instead of "patient.identifier"

**Actual behavior**
Server response with a http 403 containing the following error message:
`
`


Reproduce the R4 request at /DocumentReference?patient.identifier=... and compare it with the documented workaround using patient:Patient.identifier. Trace the chained-search handling for the DocumentReference patient parameter; done means the untyped query succeeds and returns the expected results without the multiple-resource-types error.

Written by the indexing model from the issue text.