Update DEI Working Group page to match conference poster

[lparsons]

Updates the DEI Working Group page so it matches the working group's poster and slides for the upcoming US-RSE conference. The poster's QR code links to this page.

Changes

Layout (pages/wg/dei.md only; no new CSS or includes)

• The overview now uses the poster's "Who We Are" text.
• Two cards (Bootstrap classes already used on the site) repeat the poster's panels:
  • Join Us: meeting time, both Slack channels, email, the General Interest and Suggestions forms, and the co-chairs.
  • What We Do: the poster's four areas, each linking to its section below.
• Current Focus lists the poster's recent activities, worded so they won't need regular updates.
• The video moves below the main content and now resizes with the page instead of using a fixed-size iframe.
• A Recent Posts list shows the three newest posts tagged dei, so the page picks up new spotlight posts without edits.

Content

• The focus sections are renamed to the poster's headings.
• Member-experiences content is combined into Assessing Community Inclusion, which describes the new Community Inclusion Assessment pilot. The pilot replaces the annual diversity report.
• The co-chairs now include pronouns.
• Meeting details, channels, forms, and the observance tag links from the June update are unchanged.

Preview

Built locally with bundle exec jekyll build. I checked the layout at desktop and phone widths; the cards stack on mobile. All anchors and the tags/#dei, #pride, and #black-history links resolve.

🤖 Generated with Claude Code

[lparsons]

Preview Link: https://output.circle-artifacts.com/output/job/d764d480-0c44-4c9f-89bc-7bbed0381e49/artifacts/0/usrse.github.io/wg/dei/index.html

Please review @exoticDFT @USRSE/usrse-maintainers

[exoticDFT]

Looks great! Thanks for making the updates @lparsons