Widen scaling plot card and add link to performance page

[sbryngelson]

Summary

• Widen the weak scaling plot card from 33% to 50% width on desktop for better readability
• Replace full-card clickable link with a proper link icon bar at the bottom, matching the simulation gallery card style

Test plan

• Docs build locally
• Scaling card renders at correct width
• Link icon navigates to expectedPerformance.html
• All precheck tests pass

🤖 Generated with Claude Code

[cubic-dev-ai]

No issues found across 1 file

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

[Copilot]

Pull request overview

Updates the documentation landing page scaling card layout to improve readability and align link behavior with the featured simulation cards.

Changes:

• Increase the weak scaling card width on desktop (from ~33% to 50%).
• Replace the full-card anchor with a dedicated external-link icon area at the bottom of the card.