Documentation: `EventSource`, htmx and `hx-ext="sse"`

[tylermmorton]

With the addition of the EventSource route module type, there is also basic support for the htmx sse extension in the torque/pkg/htmx sub-package as of https://github.com/tylermmorton/torque/commit/94a167a11092a658f4e33697d16b78bbddc50d58.

TODO:

• [ ] Add documentation to https://lbft.dev/server-sent-events
• [ ] Add dogfooding examples of how to use the new EventSource route module type in conjunction with htmx
  • Idea: Create a real-time viewer count component somewhere on lbft.dev
  • Idea: Poll GitHub API and create a real-time toast notification when changes are pushed to the docsite source.