Update README.md with project description and instructions

[sweep-ai]

Description

This PR updates the README.md file to provide a description of the project and instructions for installation and usage.

Summary of Changes

• Created a new README.md file at the root of the repository.
• Added a title for the project and a brief description explaining its purpose.
• Included step-by-step instructions for installation and running the project.
• Added a section describing the project structure and main components.
• Included a section highlighting the main features of the project, such as the chat functionality and PDF parsing.
• Added a section listing the technologies and libraries used in the project, such as React, Flask, and OpenAI's GPT-3.

Please review and merge this PR to provide better documentation for the project.

Fixes #7.

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