Render Human answer activity

[willmot]

• render human_mention comments as quiet activity rows in the H2 comment stream
• show “Referenced by @human to answer a question from @user”, linking the question to Slack and the user to their H2 profile
• share the established activity-row layout with Slack mention markers
• keep activity markers out of comment counts, avatar piles, and Recent Comments
• cover both activity rows in the existing Storybook comments story

Human Bot producer: https://github.com/humanmade/human-bot/pull/210

Visual

[github-actions]

🛝 Playground preview

Open PR #650 in WordPress Playground

Spins up a fresh WordPress with this PR's build of the H2 theme and demo content, logged in as admin.

Built from fc5aca5 — the preview updates on every push to this PR.

[rmccue]

Looks like a rendering issue with the avatar's alignment:

Might not be from this PR - the prior changes for migrating to Tailwind I don't think had incorporated the mini update comments.

[willmot]

@rmccue ready for review/merge. Not sure if you actually want the Playground additions, can remove those if not.

[Human]

show “Referenced by @Human to answer a question from @user”, linking the question to Slack and the user to their H2 profile

I do not need to be notified, thanks.

[rmccue]

Approved - that said I think it might be worth a follow-up PR separately to make this a little more generic, as the use of "human" eg is tied directly to the name of our bot, not to any bot that a H2 user might have (and also meant the PR accidentally pinged above - sorry about that!)

[rmccue]

Also: I would update the Playground preview here, I think it's liable to get lost if it's just in Storybook, and it's handy for people previewing H2 to see what that looks like.

[willmot]

Follow-up opened in #653 to make the activity renderer generic while preserving existing Human markers.