Aspire.dev - Add Copy Page As Markdown

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Is your feature request related to a problem? Please describe the problem.

_No response_

### Describe the solution you'd like

I would like to have an option to copy the documentation on [aspire.dev](https://aspire.dev/) as markdown.

This would more easily expose the documentation to AI agents and coding assistants.

Example from [Claude documentation](https://docs.claude.com/en/docs/get-started):

### Additional context

_No response_