Rename bstr module/feature to byte_str

[clarfonthey]

This also renames the various features to use byte_str instead of bstr.

[rustbot]

r? @Mark-Simulacrum

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[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[theemathas]

Can we also have a doc alias or something, so when someone searches for bstr (like the crate name), they also find this?

[clarfonthey]

Thank you for reminding me; I'll add those to the types and the module.

EDIT: The types already have it, so, just the module, then.

[clarfonthey]

Yeah, okay, since the types have this, adding it to the modules is just extra noise:

[clarfonthey]

Note: the rustdoc links are annoying, but I'll finagle a fix for them.

[rust-log-analyzer]

The job aarch64-gnu-llvm-21-2 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

##[endgroup]
[TIMING:end] tool::ToolBuild { build_compiler: Compiler { stage: 0, host: aarch64-unknown-linux-gnu, forced_compiler: false }, target: aarch64-unknown-linux-gnu, tool: "linkchecker", path: "src/tools/linkchecker", mode: ToolBootstrap, source_type: InTree, extra_features: [], allow_features: "", cargo_args: [], artifact_kind: Binary } -- 0.133
[TIMING:end] tool::Linkchecker { compiler: Compiler { stage: 0, host: aarch64-unknown-linux-gnu, forced_compiler: false }, target: aarch64-unknown-linux-gnu } -- 0.000
##[group]Testing stage1 Linkcheck (aarch64-unknown-linux-gnu)
core/byte_str/struct.ByteStr.html:53: broken link fragment `#method.to_ascii_uppercase` pointing to `core/byte_str/struct.ByteStr.html`
core/byte_str/struct.ByteStr.html:58: broken link fragment `#method.to_ascii_lowercase` pointing to `core/byte_str/struct.ByteStr.html`
core/byte_str/struct.ByteStr.html:1388: broken link - `core/byte_str/slice::sort_by_key`
alloc/byte_str/struct.ByteStr.html:162: broken link fragment `#method.sort_by_key` pointing to `core/primitive.slice.html`
alloc/byte_str/struct.ByteStr.html:1592: broken link fragment `#method.sort_by_key` pointing to `core/primitive.slice.html`
alloc/byte_str/struct.ByteString.html:1000: broken link fragment `#method.sort_by_key` pointing to `core/primitive.slice.html`
alloc/byte_str/struct.ByteString.html:2369: broken link fragment `#method.sort_by_key` pointing to `core/primitive.slice.html`
NOTE: if you are adding or renaming a markdown file in a mdBook, don't forget to register the page in SUMMARY.md
checked links in: 25.0s
number of HTML files scanned: 62506
number of HTML redirects found: 22211
number of links checked: 2987265
number of links ignored due to external: 185294
---
Command `/checkout/obj/build/aarch64-unknown-linux-gnu/stage1-tools-bin/linkchecker /checkout/obj/build/aarch64-unknown-linux-gnu/doc` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/tool.rs:1608:23
Executed at: src/bootstrap/src/core/build_steps/test.rs:205:77

Command has failed. Rerun with -v to see more details.
Build completed unsuccessfully in 0:32:55
  local time: Tue Aug 11 19:05:10 UTC 2026
  network time: Tue, 11 Aug 2026 19:05:10 GMT
##[error]Process completed with exit code 1.
##[group]Run echo "disk usage:"