Sprint 1: Foundation Fix - Complete

- Add tier system migration (free/pro)
- FamilyProvider with tier and memberCount
- Ready for freemium model with limits

Run migration:
psql -f drizzle/0005_tier_system.sql

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/app/FamilyProvider.tsx

@@ -75,6 +75,10 @@ export function FamilyProvider({ children: providerChildren }: { children: React
     fetchFamilyData();
   }, []);
 
+  // Check if can add more children/members based on tier limits
+  const canAddChild = () => memberCount < 2 || tier === "pro"; // free = 1 child, pro = unlimited
+  const canAddMember = () => memberCount < 2 && tier === "free" ? false : true;
+
   return (
     <FamilyContext.Provider
       value={{