fix(auth): include persona field in sign-in response

The persona field was missing from both the session object and the API
response during sign-in, causing User Settings to display an empty field
even when the user had a persona defined in the database.

gadget-code/src/controllers/api/v1/auth.ts

@@ -45,6 +45,7 @@ export class AuthApiControllerV1 extends DtpController {
         email: user.email,
         displayName: user.displayName,
         flags: user.flags,
+        persona: user.persona,
       };
 
       this.log.info("creating JSON Web Token for user session", {
@@ -69,6 +70,7 @@ export class AuthApiControllerV1 extends DtpController {
             email: user.email,
             displayName: user.displayName,
             flags: user.flags,
+            persona: user.persona,
           },
           token,
         });