feat(miniprogram): Token 常量生成脚本 + useCanvasTokens hook (E2-1 Phase 2)

- 新增 scripts/generate-tokens.ts 从 SCSS 解析 CSS 变量生成 token-values.ts
- 新增 useCanvasTokens hook 供 Canvas 组件适老化/医生端切换
- vitest include 扩展覆盖 scripts/__tests__/
- 10 单元测试覆盖 SCSS 解析和变量替换

apps/miniprogram/vitest.config.ts

@@ -4,7 +4,7 @@ import path from 'path';
 export default defineConfig({
   test: {
     environment: 'node',
-    include: ['__tests__/**/*.test.ts'],
+    include: ['__tests__/**/*.test.ts', 'scripts/__tests__/**/*.test.ts'],
     globals: true,
     setupFiles: ['__tests__/setup.ts'],
   },