Unsatisfied peer dependencies on fresh project with `3.6.1`

[MorrisonCole]

Have you read the Contributing Guidelines on issues?

• [X] I have read the Contributing Guidelines on issues.

Prerequisites

• [X] I'm using the latest version of Docusaurus.
• [X] I have tried the npm run clear or yarn clear command.
• [X] I have tried rm -rf node_modules yarn.lock package-lock.json and re-installing packages.
• [X] I have tried creating a repro with https://new.docusaurus.io.
• [X] I have read the console error message carefully (if applicable).

Description

A fair few core packages have unsatisfied peer dependencies with a fresh project on 3.6.1. This is most obvious with something like yarn 3.5.0, but also reproducable with pnpm and auto-install-peers=false.

Full set of warnings below.

Reproducible demo

https://github.com/MorrisonCole/docusaurus-peer-dependencies-repro/

Steps to reproduce

1. Run npm init docusaurus@latest
   • (use any name)
   • classic
   • TypeScript
2. (make sure yarn is available with corepack enable
3. Run yarn from the new project. Depending on the version, different warnings will be printed at this time, but you can see all peer warnings with yarn explain peer-requirements.

Expected behavior

No YN0002 warnings / missing peers.

Actual behavior

Fair few missing peers, e.g., with (yarn set version 3.5.0):

➤ YN0002: │ @docusaurus/bundler@npm:3.6.1 [fb9bc] doesn't provide react (p61e2d), requested by @docusaurus/types
➤ YN0002: │ @docusaurus/bundler@npm:3.6.1 [fb9bc] doesn't provide react-dom (p19f9f), requested by @docusaurus/types
➤ YN0002: │ @docusaurus/plugin-content-blog@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p7dbc9), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/plugin-content-docs@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p9f38b), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/plugin-content-pages@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p77e7e), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/plugin-debug@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p6f0af), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/plugin-google-analytics@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p9f6c6), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/plugin-google-gtag@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p7a09c), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/plugin-google-tag-manager@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p0011e), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/plugin-sitemap@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p93365), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/preset-classic@npm:3.6.1 [e1d64] doesn't provide @mdx-js/react (p45d1a), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/theme-search-algolia@npm:3.6.1 [38fed] doesn't provide @mdx-js/react (p4a912), requested by @docusaurus/core
➤ YN0002: │ @docusaurus/utils-common@npm:3.6.1 doesn't provide react (pc078f), requested by @docusaurus/types
➤ YN0002: │ @docusaurus/utils-common@npm:3.6.1 doesn't provide react-dom (p5bd66), requested by @docusaurus/types
➤ YN0002: │ @docusaurus/utils@npm:3.6.1 doesn't provide react (p8d75d), requested by @docusaurus/types
➤ YN0002: │ @docusaurus/utils@npm:3.6.1 doesn't provide react-dom (pb357f), requested by @docusaurus/types

Your environment

• Public source code: https://github.com/MorrisonCole/docusaurus-peer-dependencies-repro/
• Public site URL: N/A
• Docusaurus version used: 3.6.1
• Environment name and version (e.g. Chrome 89, Node.js 16.4): Chrome 130.0.6723.117, Node v20.10.0
• Operating system and version (e.g. Ubuntu 20.04.2 LTS): macOS Sequoia 15.1

Self-service

• [X] I'd be willing to fix this bug myself.

[Josh-Cena]

https://github.com/facebook/docusaurus/pull/10391 added a peer dependency of core on MDX, so all dependents of core must also peerly depend on MDX. I don't fancy this idea especially since the core should be content-agnostic. @slorber is it possible for the core to expose a plugin API that injects module aliases for bundlers?