Ultracite for Replit Agent

# Ultracite Code StandardsThis project uses **Ultracite**, a zero-config preset that enforces strict code quality standards through automated formatting and linting.## Quick Reference- **Format code**: `npx ultracite fix`- **Check for issues**: `npx ultracite check`- **Diagnose setup**: `npx ultracite doctor`Biome (the underlying engine) provides robust linting and formatting. Most issues are automatically fixable.---## Core PrinciplesWrite code that is **accessible, performant, type-safe, and maintainable**. Focus on clarity and explicit intent over brevity.### Type Safety & Explicitness- Use explicit types for function parameters and return values when they enhance clarity- Prefer `unknown` over `any` when the type is genuinely unknown- Use const assertions (`as const`) for immutable values and literal types- Leverage TypeScript's type narrowing instead of type assertions- Use meaningful variable names instead of magic numbers - extract constants with descriptive names### Modern JavaScript/TypeScript- Use arrow functions for callbacks and short functions- Prefer `for...of` loops over `.forEach()` and indexed `for` loops- Use optional chaining (`?.`) and nullish coalescing (`??`) for safer property access- Prefer template literals over string concatenation- Use destructuring for object and array assignments- Use `const` by default, `let` only when reassignment is needed, never `var`### Async & Promises- Always `await` promises in async functions - don't forget to use the return value- Use `async/await` syntax instead of promise chains for better readability- Handle errors appropriately in async code with try-catch blocks- Don't use async functions as Promise executors### React & JSX- Use function components over class components- Call hooks at the top level only, never conditionally- Specify all dependencies in hook dependency arrays correctly- Use the `key` prop for elements in iterables (prefer unique IDs over array indices)- Nest children between opening and closing tags instead of passing as props- Don't define components inside other components- Use semantic HTML and ARIA attributes for accessibility:  - Provide meaningful alt text for images  - Use proper heading hierarchy  - Add labels for form inputs  - Include keyboard event handlers alongside mouse events  - Use semantic elements (`<button>`, `<nav>`, etc.) instead of divs with roles### Error Handling & Debugging- Remove `console.log`, `debugger`, and `alert` statements from production code- Throw `Error` objects with descriptive messages, not strings or other values- Use `try-catch` blocks meaningfully - don't catch errors just to rethrow them- Prefer early returns over nested conditionals for error cases### Code Organization- Keep functions focused and under reasonable cognitive complexity limits- Extract complex conditions into well-named boolean variables- Use early returns to reduce nesting- Prefer simple conditionals over nested ternary operators- Group related code together and separate concerns### Security- Add `rel="noopener"` when using `target="_blank"` on links- Avoid `dangerouslySetInnerHTML` unless absolutely necessary- Don't use `eval()` or assign directly to `document.cookie`- Validate and sanitize user input### Performance- Avoid spread syntax in accumulators within loops- Use top-level regex literals instead of creating them in loops- Prefer specific imports over namespace imports- Avoid barrel files (index files that re-export everything)- Use proper image components (e.g., Next.js `<Image>`) over `<img>` tags### Framework-Specific Guidance**Next.js:**- Use Next.js `<Image>` component for images- Use `next/head` or App Router metadata API for head elements- Use Server Components for async data fetching instead of async Client Components**React 19+:**- Use ref as a prop instead of `React.forwardRef`**Solid/Svelte/Vue/Qwik:**- Use `class` and `for` attributes (not `className` or `htmlFor`)---## Testing- Write assertions inside `it()` or `test()` blocks- Avoid done callbacks in async tests - use async/await instead- Don't use `.only` or `.skip` in committed code- Keep test suites reasonably flat - avoid excessive `describe` nesting## When Biome Can't HelpBiome's linter will catch most issues automatically. Focus your attention on:1. **Business logic correctness** - Biome can't validate your algorithms2. **Meaningful naming** - Use descriptive names for functions, variables, and types3. **Architecture decisions** - Component structure, data flow, and API design4. **Edge cases** - Handle boundary conditions and error states5. **User experience** - Accessibility, performance, and usability considerations6. **Documentation** - Add comments for complex logic, but prefer self-documenting code---Most formatting and common issues are automatically fixed by Biome. Run `npx ultracite fix` before committing to ensure compliance.