chore(rustdoc): refresh JS toolchain with Vite+

[ubugeeei]

This PR refreshes the JavaScript tooling used by rustdoc JS tidy checks.

Vite+ | The Unified Toolchain for the Web
https://viteplus.dev/

Powered by Rust, MIT
https://github.com/voidzero-dev/vite-plus

What changed

• Replaced the rustdoc JS ESLint configs with Vite+ configuration in vite.config.ts.
• Updated tidy to run vp fmt --check before vp lint for rustdoc JavaScript.
• Kept the existing es-check and tsc checks in the tidy path.
• Promoted Oxlint correctness diagnostics to errors in the rustdoc Vite+ configs.
• Enabled unused disable directive reporting with warnings denied, so stale disable comments cannot silently remain.
• Configured oxfmt with the previous formatting contract: tabWidth: 4, printWidth: 100, and arrowParens: "avoid".
• Applied the initial oxfmt pass where it preserves the existing rustdoc JS layout intent.

Why

• Rustdoc JS checks stay integrated with the existing ./x test tidy --extra-checks=js workflow.
• The JS lint and format configuration now lives in typed vite.config.ts files instead of separate ESLint config files.
• Oxlint/Oxfmt provide a Rust-based toolchain with faster local feedback than the previous ESLint path.
• Keeping arrowParens: "avoid" preserves the previous single-argument arrow style from the ESLint arrow-parens: as-needed rule.
• Vite+ is part of the VoidZero toolchain. Since VoidZero joined Cloudflare on June 4, 2026, the upstream projects are expected to continue receiving active maintenance, with the original team still leading them and Cloudflare committing engineering resources.

Review notes

The formatter intentionally excludes js/search.js and js/src-script.js. Those files wrap large bodies in a function while keeping the body visually at top-level indentation, and oxfmt currently does not have a setting to preserve that layout. They are still covered by the Oxlint, es-check, and tsc tidy checks.

The remaining oxfmt diff is mechanical formatting output: function spacing, wrapping, object formatting, and TypeScript suppression comments adjusted after formatting.

The functional tidy changes are concentrated in the Vite+ configs and src/tools/tidy/src/extra_checks/rustdoc_js.rs.

The rust-analyzer VS Code extension changes were removed from this PR in response to review feedback. They should be proposed separately against the rust-analyzer workflow instead of being bundled with this rustdoc/tidy change.

Validation

• ./x test tidy --extra-checks=js
• Also verified earlier with the source-tree node_modules directory temporarily moved aside, matching CI's dependency layout where JS packages are installed under build/node_modules.

[rustbot]

rust-analyzer is developed in its own repository. If possible, consider making this change to rust-lang/rust-analyzer instead.

cc @rust-lang/rust-analyzer

Some changes occurred in HTML/CSS/JS.

cc @GuillaumeGomez, @lolbinarycat

rustc-dev-guide is developed in its own repository. If possible, consider making this change to rust-lang/rustc-dev-guide instead.

cc @BoxyUwU, @tshepang

tidy extra checks were modified.

cc @lolbinarycat

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @notriddle (or someone else) some time within the next two weeks.

Please see the contribution instructions for more information. Namely, in order to ensure the minimum review times lag, PR authors and assigned reviewers should ensure that the review label (S-waiting-on-review and S-waiting-on-author) stays updated, invoking these commands when appropriate:

• @rustbot author: the review is finished, PR author should check the comments and take action accordingly
• @rustbot review: the author is ready for a review, this PR will be queued again in the reviewer's queue

Why was this reviewer chosen?

The reviewer was selected based on:

• Owners of files modified in this PR: rustdoc
• rustdoc expanded to 9 candidates
• Random selection from GuillaumeGomez, camelid, lolbinarycat, notriddle

[lnicola]

For rust-analyzer what the bot said, but please split it in multiple PRs.

[lnicola]

And please shquash/rebase the rust-analyzer changes out of the history instead of reverting them.

[GuillaumeGomez]

Adding parens around single arg for closure is not great. :-/

View changes since the review

[GuillaumeGomez]

We didn't indent on purpose. ^^'

View changes since the review

[GuillaumeGomez]

Also before going any further: why should we use vite+ instead or yarn/npm? What are the gains from this switch? Nothing in your description is telling us that.

[JorgeCepeda]

Judging by the 10k contributions in the last year... This is AI-generated.

[GuillaumeGomez]

Noted.

[GuillaumeGomez]

So in this case, since there is no provided argument as to why we should switch to this tool, I'm going to close it. Feel free to open a thread on our zulip if you want it to be discussed again.