Allow users to input a requirements.txt file when creating a Python Virtual Environment

### Task Summary

In the current Python Virtual Environment implementation, users must manually enter package names and their corresponding versions, which can be time-consuming—especially when working with a large number of dependencies.

This task will enable users to provide dependencies by either pasting the contents of a requirements.txt file into a text box or uploading the .txt file directly. The system will parse the file and call the existing backend installation function to install the listed packages.

### Priority

P2 – Medium

### Task Type

- [x] Code Implementation
- [ ] Documentation
- [x] Refactor / Cleanup
- [ ] Testing / QA
- [ ] DevOps / Deployment