style(theme): 更新网站主题色彩方案与字体配置

- 调整主色调从 #1C1C1C 至 #1A1A1A，优化视觉层次
- 更新背景色系为暖白色调 (#FAFAF7, #F5F4F0 等)
- 配置中文字体栈，添加 serif 字体支持
- 优化文本颜色梯度，提升可读性
- 调整边框颜色，统一水墨风格
- 添加 Google Search Console 验证码配置项
- 新增桌面应用架构专家代理配置文件
- 重构 E2E 测试等待策略，提升稳定性
- 添加回归测试脚本，增强质量保障

src/components/sections/product-matrix-section.tsx

@@ -2,6 +2,7 @@
 
 import { motion } from 'framer-motion';
 import { ProductCard } from '@/components/ui/product-card';
+import { GeometricDecoration } from '@/components/ui/brand-visuals';
 import { PRODUCTS } from '@/lib/constants';
 import { useReducedMotion } from '@/hooks/use-reduced-motion';
 
@@ -9,8 +10,9 @@ export function ProductMatrixSection() {
   const shouldReduceMotion = useReducedMotion();
 
   return (
-    <section id="products" className="relative py-16 md:py-20 bg-[var(--color-bg-primary)]">
-      <div className="container-wide">
+    <section id="products" className="relative py-16 md:py-20 bg-[var(--color-bg-primary)] bg-texture-grid">
+      <GeometricDecoration variant="lines" />
+      <div className="container-wide relative z-10">
         <motion.div
           initial={shouldReduceMotion ? {} : { opacity: 0, y: 20 }}
           whileInView={{ opacity: 1, y: 0 }}