Leptos nightly --> stable

[zakstucke]

Really cool library!

I tried using it with leptos but seems to only work with nightly (I use stable).
The changes here move the internals over to stable.

[DanielleHuisman]

Thank you for the pull request. Could you make sure linters and tests pass?

[zakstucke]

@DanielleHuisman I've run cargo fmt, cargo check is also green.

I haven't been able to get the test environment with playright working though.
No matter what I do I can't get passed following err: