Remove duplicates and add common ignore patterns

[Danncode10]

Summary

Cleaned up the .gitignore file by removing duplicate entries, organizing ignore rules, and ensuring standard development-related files and directories (such as .env, .parcel-cache, and Thumbs.db) are properly ignored.

Motivation

Improving the .gitignore helps reduce clutter in version control, ensures unnecessary files are excluded from commits, and follows best practices to support a clean and consistent development environment across all contributors.

Change Type

• 🧹 Refactor (non-breaking improvements, no behavior change)

Checklist

• I’ve read the Contributing Guidelines
• My code matches the project’s coding style (npm run lint)
• My change introduces changes to the documentation
• I’ve updated documentation where needed
• I’ve added tests covering new behavior
• All existing and new tests pass

Related Issues

• Closes Add a standard .gitignore file to the repository #22

[MohamadSalman11]

@Danncode10 thanks for your contribution! Looks good.