🛠 Repo: Add explicit type: 'commonjs'/'module' to all package.json files

[JoshuaKGoldberg]

Tooling Suggestion Checklist

• I have tried restarting my IDE and the issue persists.
• I have pulled the latest main branch of the repository.
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Overview

In the latest versions of Node 23, I'm seeing in some packages warnings like:

(node:12365) ExperimentalWarning: Type Stripping is an experimental feature and might change at any time
(Use `node --trace-warnings ...` to show where the warning was created)
(node:12365) [MODULE_TYPELESS_PACKAGE_JSON] Warning: Module type of file:///Users/josh/repos/mocha-examples/packages/typescript/src/index.spec.ts is not specified and it doesn't parse as CommonJS.
Reparsing as ES module because module syntax was detected. This incurs a performance overhead.
To eliminate this warning, add "type": "module" to /Users/josh/repos/mocha-examples/packages/typescript/package.json.

This does not reproduce on older versions of Node, such as 20.10.0.

Proposal: let's do what the warning suggests and add explicit "type"s to the package.json files?

Additional Info

No response