Fix download only one, randomize user agents

[NotJoeMartinez]

This pull request introduces several enhancements to the yt-fts project, including version updates, improved handling of HTTP headers, and better error messaging. The most significant changes involve adding dynamic user-agent selection for HTTP requests, refining error handling, and improving subtitle extraction logic.

Version Update:

• Updated the project version from 0.1.61 to 0.1.62 in pyproject.toml and src/yt_fts/__init__.py. [1] [2]

HTTP Header Enhancements:

• Introduced a _user_agents property in src/yt_fts/download/download_handler.py to provide a list of user agents, enabling dynamic selection for HTTP headers.
• Updated get_videos_list, get_playlist_data, and get_vtt methods to use the dynamic user-agent selection via HTTP headers instead of a static 'random' value. [1] [2] [3]

Error Handling Improvements:

• Enhanced error messaging for scenarios such as missing subtitles and failed attempts, using colored console output for better readability.
• Updated warning messages to clarify errors during subtitle extraction, replacing "Error" with "Warning".

Subtitle Extraction Logic:

• Added logic to check for available subtitles and automatic captions before attempting downloads, ensuring better handling of cases where subtitles are unavailable.

Code Cleanup and Import Organization:

• Reorganized imports in src/yt_fts/download/download_handler.py for better readability and maintainability.