add transparent attribute for mod items

[yaahc]

Addresses #79260

r? @petrochenkov

[rustbot]

Some changes occurred in compiler/rustc_hir/src/attrs

cc @jdonszelmann

Some changes occurred in compiler/rustc_attr_parsing

cc @jdonszelmann

Some changes occurred in compiler/rustc_passes/src/check_attr.rs

cc @jdonszelmann

[yaahc]

This was the most obvious place to put this but it doesn't feel great, don't love all the places where I changed shit to name_and_transparent, open to suggestions for how to better thread this information through

[yaahc]

ill clean this up in the next pass, formatting got fked up in a few places >:[

[yaahc]

todo: cleanup formatting

[yaahc]

I feel like I'm probably doing this part subtly wrong.

The transparent symbol already exists and I'm using it, I tried seeing if I could stay away from it and find a way to have all the compiler internal stuff talk about it with a unique symbol (transparent_modules) but have the actual ident of the attribute be transparent but it seemed like this was controlling that. If I got that wrong lmk.

[rust-log-analyzer]

The job tidy failed! Check out the build log: (web) (plain enhanced) (plain)

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

fmt: checked 6479 files
tidy check
tidy [rustdoc_json (src)]: `rustdoc-json-types` modified, checking format version
tidy: Skipping binary file check, read-only filesystem
tidy [features]: /checkout/compiler/rustc_feature/src/unstable.rs:664: feature transparent_modules is not sorted by feature name (should be between transmute_generic_consts and transparent_unions)
tidy [features]: /checkout/compiler/rustc_feature/src/unstable.rs:664: no tracking issue for feature transparent_modules
Expected a gate test for the feature 'transparent_modules'.
Hint: create a failing test file named 'tests/ui/feature-gates/feature-gate-transparent-modules.rs',
      with its failures due to missing usage of `#![feature(transparent_modules)]`.
Hint: If you already have such a test and don't want to rename it,
      you can also add a // gate-test-transparent_modules line to the test file.
tidy [features]: Found 1 features without a gate test.
tidy [features]: /checkout/compiler/rustc_feature/src/unstable.rs:664: The stabilization version 1.92.0 of lang feature `transparent_modules` is written out but should be CURRENT_RUSTC_VERSION
tidy [features]: FAIL
removing old virtual environment
creating virtual environment at '/checkout/obj/build/venv' using 'python3.10' and 'venv'
creating virtual environment at '/checkout/obj/build/venv' using 'python3.10' and 'virtualenv'
Requirement already satisfied: pip in ./build/venv/lib/python3.10/site-packages (25.2)
linting python files
---
info: ES-Check: there were no ES version matching errors!  🎉
typechecking javascript files
tidy: The following check failed: features
Bootstrap failed while executing `test src/tools/tidy tidyselftest --extra-checks=py,cpp,js,spellcheck`
Command `/checkout/obj/build/x86_64-unknown-linux-gnu/stage1-tools-bin/rust-tidy /checkout /checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo /checkout/obj/build 4 /node/bin/npm --extra-checks=py,cpp,js,spellcheck` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/tool.rs:1549:23
Executed at: src/bootstrap/src/core/build_steps/test.rs:1280:29

Command has failed. Rerun with -v to see more details.
Build completed unsuccessfully in 0:03:20
  local time: Wed Oct 15 00:53:20 UTC 2025
  network time: Wed, 15 Oct 2025 00:53:20 GMT
##[error]Process completed with exit code 1.
##[group]Run echo "disk usage:"

[jdonszelmann]

No need for a closure here

[jdonszelmann]

With that nit, r=me for just the attributes stuff. I don't know as much about the name resolution part to sign off on that but thats for petrochenkov :)