[Feature Request] Display current context token count in ccusage statusline #454

I would like to request a feature to display the current context token count in ccusage, similar to the implementation shown in this gist:
https://gist.github.com/9wick/8c0e9dae6c191cf3d7182315a1f1a81a

When working with LLMs, it's crucial to monitor the current context size to:

• Understand how much of the context window is being used
• Optimize prompts and responses to stay within limits
• Make informed decisions about when to summarize or truncate conversations
• Prevent unexpected autocompact triggers and maintain control over context management