Improve support for trailing slashes

🚀 Feature

Add a preferTrailingSlashes option (or something similar) to docusaurus.config.js.

Have you read the Contributing Guidelines on issues?

Yes.

Motivation

If hosting documentation on GitHub Pages, a trailing slash appears in the URL when navigating to a specific Docusaurus page from outside the docs.

For instance, https://glaze.js.org/docs/introduction sends the visitor to https://glaze.js.org/docs/introduction/.

In order to keep consistency, there should be an option for sidebar links to have a trailing comma by default, without resorting to a longer sidebar item format.

[yangshun]

I think we should take a stance here and add trailing / to all Docusaurus-generated URLs. This will bridge the differences during development and deployed. cc @lex111 @slorber

[davidhagg]

I’ve noticed that the trailing slash potentially destroys internal links as well since the relative root is different. Don’t know if this is a separate bug or a side effect.