[Cursor] Add MDC rules from mdc-update branch

[blopit]

[Cursor] Add comprehensive MDC rules for development standards

Overview

This PR adds a collection of MDC (Markdown Configuration) rules to establish standardized development practices across the project. These rules provide guidance for various technologies and workflows.

Changes

• Added extensive collection of technology-specific rules in .cursor/rules/awesome-cursor-rules-mdc/
• Created comprehensive React and Next.js development guidelines in .cursor/rules/tech/frontend/react-nextjs.mdc
• Added Next.js App Router specific guidelines in .cursor/rules/tech/nextjs/app-router.mdc
• Established code review workflow standards in .cursor/rules/workflows/code-review.mdc
• Updated database configuration guidelines in .cursor/rules/database/config.mdc
• Added technology stack definition in .cursor/rules/stack/stack-definition.mdc

Benefits

• Provides consistent development standards across the project
• Improves code quality and maintainability
• Streamlines onboarding for new developers
• Establishes clear guidelines for code reviews and database configuration
• Creates a reference for best practices with various technologies

Testing

The MDC rules have been reviewed for accuracy and completeness. These are documentation files that don't require runtime testing.

Notes

This PR contains only the MDC rule changes from the original mdc-update branch, created as a clean implementation to avoid any potential issues.