PR Summary: Refactor part of HTTP files with tests (#778)

Overview:
This PR focuses on improving the stability and maintainability of the library's HTTP communication layer by refactoring core logic and introducing a robust testing suite.

Key Changes:

• Refactoring: Modularized the HTTP-related source files to improve code readability and structure.
• Unit Testing: Added comprehensive tests for HTTP components to ensure reliable communication with Eufy's backend and prevent future regressions.
• Code Quality: Cleaned up internal logic and applied consistent coding standards across the modified files.

Impact:

• Stability: Higher confidence in the API client's behavior due to new test coverage.
• Maintainability: Easier for contributors to understand and extend the HTTP module.