alt text for social images

[shawna-slh]

currently we provide a social images in resources frontmatter, e.g.:

image: /content-images/wai-media-guide/social.png

that gets processed into, e.g.,:

<meta property="og:image" content="https://www.w3.org/WAI/content-images/wai-media-guide/social.png" />

We need to add alt text for those images.

Steps, afaik:

1. add to back-end processing -- I assume for data in frontmatter to result in:

<meta property="og:image:alt" content="@@put brief alt here" />

2. add to resource template, probably after here:

description: # NEW: add a 150ish-character-description for social media # translate the description image: /content-images/wai-@@repo/social.png # NEW: image for social media image-alt: @@put brief alt here

3. Add to each resource. Not sure if there is an easy way -- might need to just add to frontmatter for every resource.

Should prioritize pages that we will announce soon, including:

• WAI-Adapt Overview (formerly Personalization) @ruoxiran
• Course List @leticiaseixas
• Update page

And ones that get Tweeted a lot, including:

• home page
• Get WAI News
• Perspectives main page