Add an API endpoint for extracting medical entities from files

```

Related tables: Api_embeddings, Api_uploadfile
Field_extraction = [“Medication”, “doctor names”]

API request:
POST
{
“file _id” : 2,
“Field_extraction” : “{Field_extraction}”
}

API response:

JSON

“Field”: “Medication_name”
“embeddings_guld “ or embeddings_id”

```