feat: 添加滚动重置插件

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plugins/scroll-reset.client.ts

@@ -0,0 +1,44 @@
+export default defineNuxtPlugin(() => {
+  if (typeof window === 'undefined') return
+
+  let observer: IntersectionObserver | null = null
+  let headings: HTMLElement[] = []
+
+  function initScrollSpy() {
+    // 清理旧的 observer
+    if (observer) observer.disconnect()
+
+    // 收集所有带 id 的标题
+    headings = Array.from(document.querySelectorAll('.prose h2[id], .prose h3[id]')) as HTMLElement[]
+    if (headings.length === 0) return
+
+    observer = new IntersectionObserver(
+      (entries) => {
+        for (const entry of entries) {
+          if (entry.isIntersecting) {
+            const id = entry.target.getAttribute('id')
+            if (id) {
+              history.replaceState(null, '', `#${id}`)
+            }
+          }
+        }
+      },
+      { rootMargin: '-80px 0px -70% 0px' }
+    )
+
+    headings.forEach(h => observer!.observe(h))
+  }
+
+  // 路由切换后重新初始化
+  const router = useRouter()
+  router.afterEach(() => {
+    nextTick(() => {
+      setTimeout(initScrollSpy, 100)
+    })
+  })
+
+  // 首次加载
+  onMounted(() => {
+    setTimeout(initScrollSpy, 100)
+  })
+})