React Patterns Core React patterns for component design, state management, and optimization. State Philosophy Avoid state variables. Prefer derived values and props. Scope state to the smallest subtree that needs it. Use discriminated unions for complex state. See state-management.md for: - Derived values over state - Component boundaries for state scoping - Context API patterns - Zustand for complex state - State machines over multiple useState Memoization Required for any O(n) operation. Memoize atomically to minimize dependency arrays. Use Loader/Inner pattern to narrow types before useMem…