8b6e38d3cb
On first chat open (or when both local and network return empty), the chat screen would render completely blank, which feels cold and broken. Prepend a single AI persona greeting as the first message so the first impression is warm. Trigger: - Final returned messages array is empty - Either network succeeds with empty result, or network fails and local is also empty Design notes: - Greeting is NOT persisted to local/network — pure UI-layer fallback. Once the user sends a real message, network has content and the greeting no longer appears. - If the user closes the app without ever sending a message and reopens, the greeting reappears (intentional: "warm first frame on each cold start"). - Rendered as an AI bubble (isFromAI: true) so the visual style matches the AI persona.