docs(glossary): add Interface glossary page

[dsk-dev-ai]

Summary

Fixes #44091.

This PR adds the missing Glossary definition for Interface, which was linked (but unresolved) from the existing Mixin and WebIDL glossary pages. It follows the structure of the existing Class glossary page.

What changed

• Added files/en-us/glossary/interface/index.md (new page)
  • title: Interface, slug: Glossary/Interface, page-type: glossary-definition, sidebar: glossarysidebar
  • Defines "interface" in WebIDL/web standards terms, notes inheritance from other interfaces and inclusion of mixin members, and how interfaces are exposed to JavaScript in browsers.
  • See also: WebIDL and Mixin glossary pages, the "Information contained in a WebIDL file" guide, and the WebIDL spec.

[github-actions]

Preview URLs (1 page)

• /en-US/docs/Glossary/Interface

External URLs (3)

URL: /en-US/docs/Glossary/Interface
Title: Interface

• https://en.wikipedia.org/wiki/Interface_(object-oriented_programming) (1 time) (Note! This may be a new URL 👀)
• https://webidl.spec.whatwg.org/ (1 time) (Note! This may be a new URL 👀)
• https://www.typescriptlang.org/docs/handbook/2/everyday-types.html (1 time) (Note! This may be a new URL 👀)

(comment last updated: 2026-08-31 18:04:35)

[Josh-Cena]

Thank you