feat(blog): restyle testimonial marquee section

[dyrpsf]

Summary

Improved the styling and UI of the testimonial marquee section on the blog home page (/blog).

Changes

• Redesigned the “What our community thinks” section to match the modern testimonial layout.
• Updated testimonial cards styling (background, shadow, typography, quote icon).
• Fixed avatar loading by using direct URLs instead of /api/proxy-image.
• Kept double-row marquee with smooth scroll and pause-on-hover.

Checks

• npm run lint
• npm run build

Fixes keploy/keploy#3440