BREAKING CHANGE: Project renamed to `download_utils` for BCR upstreaming.

A graceful switch can be done by renaming the module in `MODULE.bazel`:

```
bazel_dep(name = "download_utils", repo_name = "rules_download")
```

On Windows `ctx.symlink` actually creates hardlinks.

BREAKING CHANGE: `symlinks` in the rule is now `links`

```diff
 download_archive(
-    symlinks = {
+    links = {
         "abc.txt": "def.txt",
     }
 )
```

Allows creating symlinks in the created download repositories.

This is especially useful for cross-platform creation of symlinks.

Double down on all hermetic tooling should be provided in `tools`.

`rules_coreutils` should be the ruleset that provides hermetic coreutils,
not `rules_download`.

Users should only pay for what they use and if they never use core utilities,
we download it everytime.