Support adding existing documents to a session

src/lib/fields.ts

@@ -1,8 +1,9 @@
 import { type DocumentData, type DocumentType } from "./types";
 
-export type FieldType = "shortText" | "longText" | "toggle";
+export type FieldType = "identifier" | "shortText" | "longText" | "toggle";
 
 export type ValueForFieldType<F extends FieldType> = {
+  identifier: string;
   shortText: string;
   longText: string;
   toggle: boolean;
@@ -10,6 +11,7 @@ export type ValueForFieldType<F extends FieldType> = {
 
 function defaultValue<F extends FieldType>(fieldType: F): ValueForFieldType<F> {
   switch (fieldType) {
+    case "identifier":
     case "shortText":
     case "longText":
       return "" as ValueForFieldType<F>;