v0.2.4

First version of multi thread support

Thanks to #1353 you can now have multiple CDP connections to the same Lightpanda process.
Every CDP connection gets its own full browser, but you can still only open 1 context and 1 page at a time per connection.
Everything is cleaned up on disconnect.

https://lightpanda.io/blog/posts/how-we-built-multiclient

Dump web page in markdown format

Thanks to #1560 you can now dump a fetched page into markdown format.
Use the --dump markdown option with the fetch command.