Add Cursor AI rules for improved code generation

[burnjohn]

Adds structured Cursor rules to improve AI-assisted development:

• global.mdc: Core style rules (no semicolons, Ant Design only, theme tokens)
• frontend.mdc: React patterns, hooks, i18n, forms
• backend.mdc: Express patterns, asyncHandler, route organization

KISS approach with 3 focused files + README. All examples use actual codebase patterns.

[burnjohn]

Thanks for the excellent questions! I've addressed both comments with comprehensive improvements:

Comment 1 (Controller Pattern): You're right - the try-catch isn't "bad", just verbose. I've relabeled it and added a detailed explanation of why asyncHandler is preferred (DRY principle, consistency, maintainability).

Comment 2 (Validation): Added 7 comprehensive validation patterns:

• ObjectId validation with mongoose
• Enum/allowed values checking
• File type and size validation
• Email format validation
• String sanitization and trimming
• Conditional business logic validation

Also added a reference to the actual validators/blogValidator.js file for real-world examples from the codebase.

All changes maintain the project's style guide (no semicolons, single quotes).

[burnjohn]

Updates Pushed! 🎉

I've addressed both of your review comments with comprehensive improvements:

Comment 1: "Is it really a bad example?"

Resolution: You're absolutely right! The try-catch pattern isn't "bad" - it's valid code that works correctly.

Changes made:

• Changed label from "Bad" to "Verbose - manual try-catch (repetitive across controllers)"
• Added explanation section covering:
  • DRY principle - Centralizes error handling
  • Consistency - Uniform handling across controllers
  • Less boilerplate - Eliminates repetition
  • Maintainability - Single place to update logic

Comment 2: "Can you suggest any other validation"

Resolution: Expanded the Validation section significantly!

Added 7 validation patterns:

1. Basic Field Validation (improved existing example)
2. ObjectId Validation - MongoDB ID format checking with mongoose.Types.ObjectId.isValid()
3. Enum/Allowed Values - Category whitelist validation
4. File Type & Size - MIME type and 5MB limit checks
5. Email Validation - Regex-based format validation
6. String Sanitization - Trim and length limiting
7. Conditional Validation - Business logic constraints (e.g., "must be reviewed before publishing")

Bonus: Added reference to validators/blogValidator.js for real-world examples from our actual codebase.

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All changes follow project conventions (no semicolons, single quotes). Ready for another review! ✨