MED-56: show specific error when job taken, other small improvements (#58)

* show specific error when job taken, other small improvements

* enum name case

* enum value case, actually

public/locales/en/doctor.json

@@ -39,6 +39,10 @@
         "title": "Confirm publishing summary",
         "description": "When confirmed, the summary will be published to the patient."
     },
+    "error": {
+        "UNKNOWN": "Something went wrong",
+        "JOB_ASSIGNED": "Job already selected"
+    },
     "updateFeedbackSuccess": "Summary updated",
     "updateFeedbackLoading": "Updating summary...",
     "updateFeedbackError": "Failed to update summary",