Implement strip_circumfix lib feature

[yotamofek]

Tracking issue: #147946

[rustbot]

r? @ibraheemdev

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[rust-log-analyzer]

The job x86_64-gnu-tools failed! Check out the build log: (web) (plain enhanced) (plain)

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

 Documenting proc_macro_test v0.1.0 (/checkout/tests/rustdoc-gui/src/proc_macro_test)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.81s
   Generated /checkout/obj/build/x86_64-unknown-linux-gnu/test/rustdoc-gui/doc/proc_macro_test/index.html
npm WARN deprecated puppeteer@22.15.0: < 24.10.2 is no longer supported
npm ERR! code E409
npm ERR! 409 Conflict - GET https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz

npm ERR! A complete log of this run can be found in: /home/user/.npm/_logs/2025-10-22T11_12_26_794Z-debug-0.log
npm install did not exit successfully

thread 'main' (59853) panicked at src/tools/rustdoc-gui-test/src/main.rs:63:10:
unable to install browser-ui-test: Custom { kind: Other, error: "npm install returned exit code exit status: 1" }
stack backtrace:
   0: __rustc::rust_begin_unwind
             at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:698:5
   1: core::panicking::panic_fmt
             at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/panicking.rs:75:14

[yotamofek]

npm ERR! code E409
npm ERR! 409 Conflict - GET https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz

Looks quite spurious :)