refactor(ui): switch remaining raw CTA pills to CTAButton across 5 pages

- about/contact 补 CTAButton import，移除变 unused 的 ArrowUpRight/ArrowRight

- products/standalone 次链接 StaticLink → CTAButton secondary

- 统一品牌 ArrowRight 签名与 200-300ms 过渡，保留原始尺寸

src/app/(marketing)/news/news-content-v3.tsx

@@ -253,12 +253,9 @@ export default function NewsContentV3({ news, pageCopy }: { news?: NewsItem[]; p
               <CTAButton href="/contact" dataTestId="news-bottom-cta">
                 联系我们
               </CTAButton>
-              <a
-                href="/about"
-                className="inline-flex items-center justify-center gap-3 px-12 py-6 font-semibold text-base text-ink border border-border-primary rounded-full hover:border-border-secondary hover:bg-bg-secondary transition-all duration-300"
-              >
+              <CTAButton href="/about" variant="secondary" className="px-12 py-6">
                 了解公司
-              </a>
+              </CTAButton>
             </div>
           </ScrollReveal>
         </div>