Add "block-selectors" docs to TOC and manifest.

[Soean]

What?

Fixes #49469

Adds block selectors docs to the TOC file and adds the generated manifest.

After merging, it should be available via: https://developer.wordpress.org/block-editor/reference-guides/block-api/block-selectors/

[github-actions]

Flaky tests detected in 1dbd073.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/4563528141
📝 Reported issues:

• [Flaky Test] doesn't throw a block error when clicking on a link #47747 in /test/e2e/specs/site-editor/template-part.spec.js

[gziolo]

Good catch! This is a new feature that won’t be available in WordPress core until 6.3 (late August), what would be the best way to highlight it in https://github.com/WordPress/gutenberg/blob/trunk/docs/reference-guides/block-api/block-selectors.md?

[gziolo]

Is it sorted by name?

[aaronrobertshaw]

Thanks for fixing this up @gziolo 👍

what would be the best way to highlight it in https://github.com/WordPress/gutenberg/blob/trunk/docs/reference-guides/block-api/block-selectors.md?

In some of the components package readmes where there are experimental components, they use a callout alert at the top of the readme. Perhaps we could do something here in block-selectors.md?

Something like adding the following beneath the title:

<div class="callout callout-alert">
	This API was stabilized in Gutenberg 15.5 and is planned for core release
	in WordPress 6.3. To use this prior to WordPress 6.3, you will need to install
	and activate Gutenberg >= 15.5.
</div>
<br />

[gziolo]

Thanks for fixing this up @gziolo 👍

It’s actually @Soean 😃

In some of the components package readmes where there are experimental components, they use a callout alert at the top of the readme. Perhaps we could do something here in block-selectors.md?

Something like adding the following beneath the title:

<div class="callout callout-alert">
	This API was stabilized in Gutenberg 15.5 and is planned for core release
	in WordPress 6.3. To use this prior to WordPress 6.3, you will need to install
	and activate Gutenberg >= 15.5.
</div>
<br />

That would work until it’s released in WordPress core 👍

It would be also good in general to always include a paragraph next to the page title explaining when the feature becomes available in WordPress core. I didn’t think about it before.

[aaronrobertshaw]

It’s actually @Soean 😃

🤦 So it is. Clearly my caffeine levels had dipped too low ☕

That would work until it’s released in WordPress core 👍

I've taken the liberty to push a commit adding a callout that the selectors API won't be released in core until WordPress 6.3.

I hope that's okay @Soean! Feel free to tweak the wording if desired.

[gziolo]

Excellent, that looks great now 🙌🏻

[gziolo]

I don't see a line break added in other places, but we can verify once the handbook updates.

[aaronrobertshaw]

I took the <br /> from the components package examples. IIRC, when testing it locally, without the line break the text moved up with no space between it and the callout. That could have been just previewing the markdown though 🤔

[gziolo]

So nice, I like it!

I don't think the <br /> makes any difference here. It probably gets replaced with an empty <p></p> and nothing changes when I remove it in Browser Console.

[gziolo]

I opened #49792 with improvements for the block editor handbook. I also remove the <br /> there. I also included the Selectors page in the Block API Reference index page.