1. Performance & Rendering - Const-First : Every widget that can be MUST be . - Lazy Rendering : Use or for lists 10 items. - Repaint Boundaries : Wrap complex animations in . - Isolate Parsing : Use or for JSON 1MB. - BuildContext Safety : Check before using across async gaps. 2. Design Tokens (Theming) Use , , , and . NEVER hardcode raw values. - Colors : Use or . Support light/dark modes. - Spacing : Use (8), (16), etc. Use for gaps. - Radius : Use (12) for consistent rounding. - Typography : Use . Support text scaling. 3. Reusable Components - Single Responsibility : Each component has on…