refactor: change kiosk parameter from Option<bool> to bool

Simplifies the setup API by making kiosk mandatory at the protocol level,
with platform-specific filtering applied at the database layer.

web/projects/setup-wizard/src/app/services/state.service.ts

@@ -72,6 +72,7 @@ export class StateService {
     await this.api.attach({
       guid: this.dataDriveGuid,
       password: password ? await this.api.encrypt(password) : null,
+      kiosk: this.kiosk,
     })
   }
 
@@ -106,6 +107,7 @@ export class StateService {
       name,
       hostname,
       recoverySource,
+      kiosk: this.kiosk,
     })
   }