Should close#8809.
# Description
this PR uses the automatically loaded library from the tests by
replacing `use std.nu ...` with `use std ...`.
the `README` has been updated by
- removing the very deprencated "concrete examples"
- fixing the `use std` and the "run the tests" sections
the `README` can be previewed
[here](https://github.com/amtoine/nushell/blob/refactor/stdlib/use-std-in-tests-and-update-readme/crates/nu-std/README.md)
👍
# User-Facing Changes
```
$nothing
```
# Tests + Formatting
- 🟢 `toolkit test stdlib`
# After Submitting
```
$nothing
```
# Description
as we now have a prelude thanks to #8627, i'd like to work on the
structure of the library 😋
and i think the first step is to make it a true standalone crate 😏
this PR
- moves all the library from `crates/nu-utils/standard_library/` to
`crates/nu-std/`
- moves the `rust` loading code from `src/run.rs` to
`crates/nu-std/src/lib.rs`