Auto merge of #107498 - JohnTitor:rollup-2i6g4uk, r=JohnTitor

Auto merge of #107498 - JohnTitor:rollup-2i6g4uk, r=JohnTitor

Rollup of 8 pull requests

Successful merges:

 - #107245 (Implement unsizing in the new trait solver)
 - #107445 (Remove `GenFuture` from core)
 - #107473 (Update books)
 - #107476 (rustdoc: remove unnecessary wrapper `div.item-decl` from HTML)
 - #107477 (Migrate last part of CSS themes to CSS variables)
 - #107479 (Use `ObligationCtxt::new_in_snapshot` in `satisfied_from_param_env`)
 - #107482 (rustdoc: remove meta keywords from HTML)
 - #107494 (fix link in std::path::Path::display())

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup