Migrate cursor rules (#12646)

Migrating rules to new format but they should be re-written entirely, I
don't think they help much and are not auto-included (except
architecture)

.cursor/rules/README.mdc

@@ -0,0 +1,137 @@
+---
+description: 
+globs: 
+alwaysApply: false
+---
+# Twenty Development Rules
+
+This directory contains Twenty's development guidelines and best practices in the modern Cursor Rules format (MDC). These rules are automatically applied based on file patterns and provide context-aware guidance to AI assistants.
+
+## Rules Overview
+
+### Core Guidelines
+- **architecture.mdc** - Project overview, technology stack, and infrastructure setup (Always Applied)
+- **nx-rules.mdc** - Nx workspace guidelines and best practices (Auto-attached to Nx files)
+
+### Code Quality
+- **typescript-guidelines.mdc** - TypeScript best practices and conventions (Auto-attached to .ts/.tsx files)
+- **code-style.mdc** - General coding standards and style guide (Auto-attached to code files)
+- **file-structure.mdc** - File and directory organization patterns (Auto-attached to config files)
+
+### React Development
+- **react-general-guidelines.mdc** - Core React development principles (Auto-attached to React files)
+- **react-state-management.mdc** - State management approaches with Recoil (Auto-attached to state files)
+
+### Testing & Quality
+- **testing-guidelines.mdc** - Testing strategies and best practices (Auto-attached to test files)
+
+### Internationalization
+- **translations.mdc** - Translation workflow and i18n setup (Auto-attached to locale files)
+
+## How Rules Work
+
+### Automatic Attachment
+Rules are automatically included in your AI context based on file patterns (globs). When you work on TypeScript files, the TypeScript guidelines are automatically loaded.
+
+### Manual Reference
+You can manually reference any rule using the `@ruleName` syntax:
+- `@nx-rules` - Include Nx-specific guidance
+- `@react-general-guidelines` - Load React best practices
+- `@testing-guidelines` - Get testing recommendations
+
+### Rule Types Used
+- **Always Applied** - Loaded in every context (architecture.mdc, README.mdc)  
+- **Auto Attached** - Loaded when matching file patterns are referenced
+- **Agent Requested** - Available for AI to include when relevant
+- **Manual** - Only included when explicitly mentioned
+
+## Development Commands
+
+### Frontend Commands
+```bash
+# Testing
+npx nx test twenty-front                    # Run unit tests
+npx nx storybook:build twenty-front         # Build Storybook
+npx nx storybook:serve-and-test:static     # Run Storybook tests
+
+# Development
+npx nx lint twenty-front                    # Run linter
+npx nx typecheck twenty-front               # Type checking
+npx nx run twenty-front:graphql:generate    # Generate GraphQL types
+```
+
+### Backend Commands
+```bash
+# Database
+npx nx database:reset twenty-server         # Reset database
+npx nx run twenty-server:database:init:prod # Initialize database
+npx nx run twenty-server:database:migrate:prod # Run migrations
+
+# Development
+npx nx run twenty-server:start             # Start the server
+npx nx run twenty-server:lint              # Run linter (add --fix to auto-fix)
+npx nx run twenty-server:typecheck         # Type checking
+npx nx run twenty-server:test              # Run unit tests
+npx nx run twenty-server:test:integration:with-db-reset # Run integration tests
+
+# Migrations
+npx nx run twenty-server:typeorm migration:generate src/database/typeorm/core/migrations/[name] -d src/database/typeorm/core/core.datasource.ts
+
+# Workspace
+npx nx run twenty-server:command workspace:sync-metadata -f  # Sync metadata
+```
+
+## Usage Guidelines
+
+### For Developers
+- Rules are automatically applied based on file context
+- Check rule descriptions to understand when they're activated
+- Use manual references (`@ruleName`) for additional context
+- Keep rules updated as the codebase evolves
+
+### For AI Assistants
+- Rules provide consistent guidance across conversations
+- Use rule context to maintain coding standards
+- Reference specific rules when making recommendations
+- Apply rule principles in code suggestions and reviews
+
+## Contributing to Rules
+
+### Adding New Rules
+1. Create a new `.mdc` file in this directory
+2. Include proper metadata headers with description and globs
+3. Write clear, actionable guidelines with examples
+4. Test the rule with relevant file patterns
+5. Update this README if needed
+
+### Updating Existing Rules
+1. Modify the rule content while preserving metadata
+2. Test changes with affected file patterns
+3. Ensure consistency with other rules
+4. Update examples and best practices as needed
+
+## Rule Format Reference
+
+Each rule file uses the MDC format with metadata:
+
+```markdown
+---
+description: Brief description of the rule's purpose
+globs: ["**/*.ts", "**/*.tsx"]  # File patterns for auto-attachment
+alwaysApply: false              # Whether to always include this rule
+---
+
+# Rule Title
+
+Rule content in Markdown format...
+```
+
+## Migration from Legacy Format
+
+The rules have been migrated from the legacy `.md` format to the modern `.mdc` format, providing:
+- Better context awareness through file pattern matching
+- Improved organization with metadata headers
+- More flexible rule application strategies
+- Enhanced integration with Cursor's AI features
+
+For the most up-to-date version of these guidelines, always refer to the files in this directory.