Cross-Platform Athlete Mindset App

I’m looking to have a fully featured mobile application built in Flutter so it can ship simultaneously to iOS and Android while still feeling completely native. The product centres on a 90-question assessment that feeds an AI-assisted rules engine, producing a personalised 20-week mental-performance plan for each athlete. I already have the assessment content and exercise templates; what I need is the system that:

• lets me manually update or bulk-generate new questions, programs, and activities with AI support
• restricts that authoring tool to Trainers only, while still giving Athletes, Parents, and Coaches their own portals to view plans, track progress, and exchange feedback
• houses a growing exercise library featuring Visualization techniques, Breathing exercises, Goal-setting activities, plus modules on Concentration, Focus, Mindset, and Recovery
• tracks focus, confidence, and resilience over time and presents that data in clean, easy-to-read dashboards

I care deeply about a professional UI: clear hierarchy, uncluttered screens, and typography that speaks to competitive athletes. If you have experience with Flutter, Firebase (or an equally scalable backend), and integrating on-device AI or cloud-based LLM calls for content generation, I’d love to see how you would structure the architecture, data models, and release roadmap. Please outline:

1. Your proposed tech stack around Flutter, any preferred state-management pattern, and how you’ll ensure native-level performance.
2. How you’ll secure role-based portals and the Trainer-only content builder.
3. A brief plan for launching an MVP and iterating toward full functionality.

Demo links or code samples from previous cross-platform apps are a plus so I can assess code clarity and design sensibility.