feat: integrate text streaming, action cards, and layout overlapping fixes
- feat(server, chatbot): Implement NDJSON streaming to surface AI typing progress in real-time.
- feat(chatbot): Automatic rendering of AI output list ([INTERNAL_ID: uuid]) into Action Cards and pill buttons.
- fix(chatbot): Prevent the ghosting phenomenon (empty chat balloons) by creating synthetic 'Prepared Action' balloons.
- fix(chatbot): Clean excess messages automatically (auto-hide) once AI sends the latest reply.
- fix(layout): Move the NotificationCenter and Toast bells to the left whenever the AI Window is open so as not to cover the Send button.
- chore(db): Change the strict system prompt in sqlite to 'BRIEF SUMMARIES ENCOURAGED' so that the AI is not stingy in speaking.