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+# SQL Chat - Development Guide
+
+## Build/Run Commands
+- Development: `pnpm dev` (or `pnpm nodb` without DB, `pnpm usedb` with DB)
+- Build: `pnpm build`
+- Production: `pnpm start`
+- Lint: `pnpm lint`
+- Database: `pnpm prisma migrate dev` (setup), `pnpm prisma db seed` (seed)
+
+## Code Style Guidelines
+- **Formatting**: 140 char width, double quotes, semicolons (Prettier)
+- **TypeScript**: Strict types, interfaces for structure, generics when appropriate
+- **Components**: Functional components with hooks, PascalCase naming
+- **Imports**: External libs first, followed by internal modules with @/ alias
+- **Naming**: PascalCase for components/interfaces, camelCase for variables/functions
+- **Functions**: Descriptive verb-noun naming (handleClick, fetchData)
+- **Error Handling**: try/catch blocks with toast notifications for user-facing errors
+- **File Structure**: Feature-based organization in /components, /types, /store
+
+## State Management
+- Zustand for global state
+- React hooks for component state
+- TypeScript types for state shape
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