Rollup of 12 pull requests
Successful merges:
- #84013 (Replace all `fmt.pad` with `debug_struct`)
- #84119 (Move `sys::vxworks` code to `sys::unix`)
- #84212 (Replace `Void` in `sys` with never type)
- #84251 (fix 'const-stable since' for NonZeroU*::new_unchecked)
- #84301 (Document that `index` and `index_mut` can panic)
- #84365 (Improve the docstrings of the `Lto` struct.)
- #84378 (Fix broken doc link)
- #84379 (Add GAT related tests)
- #84380 (Write Rustdoc titles like "x in crate::mod - Rust")
- #84390 (Format `Struct { .. }` on one line even with `{:#?}`.)
- #84393 (Support `x.py doc std --open`)
- #84406 (Remove `delete` alias from `mem::drop`.)
Failed merges:
- #84387 (Move `sys_common::poison` to `sync::poison`)
r? `@ghost`
`@rustbot` modify labels: rollup
71965ab4d0