CHW-4507 TrafficViewNameRequired

saved traffic view requires a non-empty "name" field so it can be identified in the UI

Default message: saved traffic view requires a non-empty “name” field so it can be identified in the UI
HTTP status: 400 (client)

Problem. POST /api/traffic/views returned 400. Cause. The JSON body was missing the name field, or name was an empty / whitespace-only string. Saved views are identified by name in the UI so this is required. Fix. Send a non-empty name. HTTP 400.