feat: 添加图标和路由配置

- 新增多个 SVG 图标文件
- 添加 `/demo/icons` 路由配置，用于图标预览

src/assets/svg/xt-intelligence.svg

@@ -0,0 +1,3 @@
+<svg width="24" height="24" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path d="M4.5 16.3291L11 20.083V12.3916L4.5 8.63868V16.3291ZM13 12.3916V20.083L19.5 16.3291V8.63868L13 12.3916ZM8.48535 12.5498C8.95892 12.2657 9.57329 12.42 9.85742 12.8936C10.1414 13.3671 9.98816 13.9815 9.51465 14.2656L7.01465 15.7656L6.92383 15.8135C6.46514 16.0288 5.90891 15.8658 5.64258 15.4219C5.35861 14.9483 5.51184 14.3339 5.98535 14.0498L8.48535 12.5498ZM14.1426 12.8936C14.4267 12.42 15.0411 12.2657 15.5146 12.5498L18.0146 14.0498L18.0996 14.1074C18.5055 14.4108 18.6236 14.978 18.3574 15.4219C18.0911 15.8658 17.5349 16.0288 17.0762 15.8135L16.9854 15.7656L14.4854 14.2656C14.0118 13.9815 13.8586 13.3671 14.1426 12.8936ZM5.5 6.90724L12 10.6602L18.499 6.90724L12 3.15431L5.5 6.90724ZM11 8.40822V5.40822C11 4.85593 11.4477 4.40822 12 4.40822C12.5523 4.40822 13 4.85593 13 5.40822V8.40822C12.9997 8.96028 12.5521 9.40822 12 9.40822C11.4479 9.40822 11.0003 8.96028 11 8.40822ZM21.5 16.9072C21.5 17.2645 21.3094 17.5948 21 17.7734L12.5 22.6807C12.1906 22.8593 11.8094 22.8593 11.5 22.6807L3 17.7734C2.69062 17.5948 2.5 17.2645 2.5 16.9072V6.90724C2.50009 6.55007 2.69067 6.21962 3 6.04103L11.5 1.1338L11.6191 1.07521C11.9036 0.95803 12.2293 0.977555 12.5 1.1338L21 6.04103C21.3093 6.21962 21.4999 6.55007 21.5 6.90724V16.9072Z" fill="currentColor"/>
+</svg>