feat(build): split rendering index.html from building index.json

[fiji-flo]

Important

Deprecation notice
Rendering index.html files as part of the build command is now DEPRECATED, and will no longer be supported in Yari v3. To resolve this warning, add the -n (--nohtml) option.

Summary

(MP-1174 e.a.)

Problem

Currently, building the index.json files and rendering the index.html files happens in a single step via the yarn build command. Although it's possible to only build the index.json files via yarn build -n, it is not possible to only render the index.html files.

Solution

1. Split rendering the index.html files into a separate command (yarn render:html).
2. Introduce a new explicit command for building the JSON files for docs (yarn build:docs).
3. Reuse the render:html command to render static pages (aka "SPAs"), by ensuring the corresponding builds produce index.jsons (that just contain a pageTitle and a url for now).
4. Show a deprecation warning (see above) when yarn build is called without the -n flag.

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Screenshots

(No visual change.)

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How did you test this change?

Ran a full build locally on main and on this branch, and compared the resulting build output. The only changes identified were as follows:

• There are now index.json files for all static pages ("SPAs").
• The og:url field now contains the correct URL for static pages ("SPAs"), instead of the base URL.
• All index.jsons now contain a url field, which is replicated in the hydration data of the index.html, but not part of the metadata.json.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[caugner]

This is now deployed to stage.

[fiji-flo]

This looks good. Should we get it on stage one more time and then merge?

[caugner]

Should we get it on stage one more time and then merge?

This is still deployed on stage, since 2024-06-14.