feat(archive): 文章折叠——首页 6 篇+归档年月折叠+书架年折叠

①首页 PostList limit=6 + 「全部文章 →」双轨入口（用户拍板 6 篇）
②/archives 年 <details>（最新年 open，summary「2026 · N 篇」+▸ 自绘
箭头）+ 年内按月分组小标题；零 JS 依赖、内容全在 DOM（SEO
无损）③/books 年折叠（色脊/书封渲染零改动）④E2E +3 断言
（首页≤6+入口/归档 open 唯一+月分组/书架年组不变量）

E2E 弦键竞态根治：折叠批的多次导航扰动 g-chords 时序——洁净起
点（先回稳定页）再测弦，测试意图不依赖前序状态，37/37 连跑稳定

车道：op-gitea（lint 43 页 0/0/0）；收编复验首页 6 行+入口/归档
1 年开 12 月组/书架年折叠/en 轨全过

验证: E2E 37/37 连跑两次；content-lint 0/0/0；首页/归档/书架/
en 四页 playwright 实测

Spec: none (折叠批，车道级交付)

Co-authored-by: GLM-5.3

src/components/PostList.astro

@@ -1,6 +1,9 @@
 ---
-// 年份分组 + 轨道分节的文章列表（首页与 /archives/ 共用）
+// 年份分组 + 轨道分节的文章列表（首页与归档页共用）
 // 轨道标签单一事实源：content.config 的 POST_TRACKS，此处不另立词表
+// 双形态（2026-11-02 用户拍板折叠需求）：
+//   默认形态 = 首页/列表平铺（年 → 轨道分节），可 limit 截断 + moreHref 出口
+//   fold 形态 = 归档页：按年 <details>（最新年默认开）+ 年内按月分组，零 JS 原生折叠
 import type { CollectionEntry } from 'astro:content';
 import { POST_TRACKS, type PostCategory } from '../content.config';
 import { t } from '../i18n/ui';
@@ -11,8 +14,15 @@ interface Props {
   locale?: 'zh' | 'en';
   /** slug → 译题（en 列表显示英文标题，视觉复核范围外观察） */
   titleOverrides?: Record<string, string>;
+  /** 截断条数（首页 6 篇）；缺省全量 */
+  limit?: number;
+  /** 截断后的「全部文章 →」出口链接；缺省不渲染 */
+  moreHref?: string;
+  /** true = 归档折叠形态：按年 details（最新年开）＋年内按月分组 */
+  fold?: boolean;
 }
-const { posts, locale = 'zh', titleOverrides } = Astro.props;
+const { posts, locale = 'zh', titleOverrides, limit, moreHref, fold = false } = Astro.props;
+const visible = typeof limit === 'number' ? posts.slice(0, limit) : posts;
 // 轨道标签走字典（en 首页复用本组件时的双语位）；zh 保持原词表语义
 const TRACK_LABEL: Record<PostCategory, string> = {
   reading: t('category_reading', locale),
@@ -22,59 +32,125 @@ const TRACK_LABEL: Record<PostCategory, string> = {
 const hrefOf = (id: string) => (locale === 'en' ? `/en/archives/${id}/` : `/archives/${id}/`);
 
 const byYear = new Map<number, CollectionEntry<'posts'>[]>();
-for (const post of posts) {
+for (const post of visible) {
   const year = post.data.pubDate.getUTCFullYear();
   const bucket = byYear.get(year);
   if (bucket) bucket.push(post);
   else byYear.set(year, [post]);
 }
+const units = t('unit_posts', locale);
 const mmdd = (d: Date) =>
   `${String(d.getUTCMonth() + 1).padStart(2, '0')}-${String(d.getUTCDate()).padStart(2, '0')}`;
+// 月分组标签：zh「2026 年 11 月」/ en「November 2026」（UTC，与年份口径一致）
+const monthLabel = (d: Date) =>
+  locale === 'zh'
+    ? `${d.getUTCFullYear()} 年 ${d.getUTCMonth() + 1} 月`
+    : `${d.toLocaleString('en-US', { month: 'long', timeZone: 'UTC' })} ${d.getUTCFullYear()}`;
+const byMonth = (list: CollectionEntry<'posts'>[]) => {
+  const m = new Map<string, CollectionEntry<'posts'>[]>();
+  for (const post of list) {
+    const key = `${post.data.pubDate.getUTCFullYear()}-${post.data.pubDate.getUTCMonth()}`;
+    const bucket = m.get(key);
+    if (bucket) bucket.push(post);
+    else m.set(key, [post]);
+  }
+  return [...m.entries()];
+};
 ---
 
-<div class="post-list">
-  {[...byYear.entries()].map(([year, list]) => (
-    <section class="year-block" aria-label={`${year} 年文章`}>
-      <h2 class="year">{year}</h2>
-      {(Object.keys(POST_TRACKS) as PostCategory[]).map((cat) => {
-        const rows = list.filter((post) => post.data.category === cat);
-        if (rows.length === 0) return null;
-        return (
-          <div class="track-block">
-            <h3 class="track">
+{fold ? (
+  <div class="post-list post-list-fold">
+    {[...byYear.entries()].map(([year, list], i) => (
+      <details class="year-fold" open={i === 0}>
+        <summary class="year-summary">
+          <span class="year-num">{year}</span>
+          <span class="year-count mono">· {list.length} {units}</span>
+        </summary>
+        <div class="year-body">
+          {byMonth(list).map(([key, rows]) => (
+            <section class="month-block">
+              <h3 class="month-head">
+                <span>{monthLabel(rows[0].data.pubDate)}</span>
+                <span class="mono month-count">· {rows.length} {units}</span>
+              </h3>
+              <ul>
+                {rows.map((post) => (
+                  <li>
+                    <a class="row tap" href={hrefOf(post.id)}>
+                      {post.data.category === 'reading' && (
+                        <i
+                          class="emo"
+                          style={`background:${post.data.mood ?? 'var(--mood)'}`}
+                          title="情绪色"
+                          aria-hidden="true"
+                        />
+                      )}
+                      <span class="row-title">{titleOverrides?.[post.id] ?? post.data.title}</span>
+                      {post.data.category !== 'reading' &&
+                        post.data.tags.map((tag) => <code class="tag">{`#${tag}`}</code>)}
+                      <time class="row-date" datetime={post.data.pubDate.toISOString()}>
+                        {mmdd(post.data.pubDate)}
+                      </time>
+                    </a>
+                  </li>
+                ))}
+              </ul>
+            </section>
+          ))}
+        </div>
+      </details>
+    ))}
+  </div>
+) : (
+  <div class="post-list">
+    {[...byYear.entries()].map(([year, list]) => (
+      <section class="year-block" aria-label={`${year} 年文章`}>
+        <h2 class="year">{year}</h2>
+        {(Object.keys(POST_TRACKS) as PostCategory[]).map((cat) => {
+          const rows = list.filter((post) => post.data.category === cat);
+          if (rows.length === 0) return null;
+          return (
+            <div class="track-block">
+              <h3 class="track">
                 {TRACK_LABEL[cat]}
                 {cat === 'reading' && (
                   <a class="shelf-link" href={locale === 'en' ? '/en/books/' : '/books/'}>{locale === 'en' ? 'Books →' : '书架 →'}</a>
                 )}
               </h3>
-            <ul>
-              {rows.map((post) => (
-                <li>
-                  <a class="row tap" href={hrefOf(post.id)}>
-                    {cat === 'reading' && (
-                      <i
-                        class="emo"
-                        style={`background:${post.data.mood ?? 'var(--mood)'}`}
-                        title="情绪色"
-                        aria-hidden="true"
-                      />
-                    )}
-                    <span class="row-title">{titleOverrides?.[post.id] ?? post.data.title}</span>
-                    {cat !== 'reading' &&
-                      post.data.tags.map((tag) => <code class="tag">{`#${tag}`}</code>)}
-                    <time class="row-date" datetime={post.data.pubDate.toISOString()}>
-                      {mmdd(post.data.pubDate)}
-                    </time>
-                  </a>
-                </li>
-              ))}
-            </ul>
-          </div>
-        );
-      })}
-    </section>
-  ))}
-</div>
+              <ul>
+                {rows.map((post) => (
+                  <li>
+                    <a class="row tap" href={hrefOf(post.id)}>
+                      {cat === 'reading' && (
+                        <i
+                          class="emo"
+                          style={`background:${post.data.mood ?? 'var(--mood)'}`}
+                          title="情绪色"
+                          aria-hidden="true"
+                        />
+                      )}
+                      <span class="row-title">{titleOverrides?.[post.id] ?? post.data.title}</span>
+                      {cat !== 'reading' &&
+                        post.data.tags.map((tag) => <code class="tag">{`#${tag}`}</code>)}
+                      <time class="row-date" datetime={post.data.pubDate.toISOString()}>
+                        {mmdd(post.data.pubDate)}
+                      </time>
+                    </a>
+                  </li>
+                ))}
+              </ul>
+            </div>
+          );
+        })}
+      </section>
+    ))}
+    {moreHref && (
+      <p class="more-row">
+        <a class="more-link tap" href={moreHref}>{t('home_more_posts', locale)}</a>
+      </p>
+    )}
+  </div>
+)}
 
 <style>
   .year-block + .year-block { margin-top: var(--space-5); }
@@ -159,4 +235,62 @@ const mmdd = (d: Date) =>
     font-variant-numeric: tabular-nums;
     white-space: nowrap;
   }
+  .more-row { margin: var(--space-3) 0 0; text-align: right; }
+  .more-link {
+    font-family: var(--font-mono);
+    font-size: 13px;
+    color: var(--accent);
+    border-bottom: 1px solid transparent;
+  }
+  .more-link:hover { border-bottom-color: var(--accent); }
+
+  /* ---- 归档折叠形态（fold）---- */
+  .year-fold { border-top: 1px solid var(--line); }
+  .year-fold:last-child { border-bottom: 1px solid var(--line); }
+  .year-summary {
+    display: flex;
+    align-items: baseline;
+    gap: 0.4rem;
+    padding: var(--space-2) 0;
+    cursor: pointer;
+    list-style: none;
+    color: var(--ink-2);
+  }
+  .year-summary::-webkit-details-marker { display: none; }
+  .year-summary::before {
+    content: '▸';
+    font-size: 11px;
+    color: var(--ink-4);
+    transition: transform var(--dur) var(--ease);
+    transform-origin: 50% 50%;
+    display: inline-block;
+    width: 1em;
+  }
+  .year-fold[open] > .year-summary::before { transform: rotate(90deg); }
+  .year-summary:hover { color: var(--ink-1); }
+  .year-num { font-size: 15px; font-weight: 600; font-variant-numeric: tabular-nums; }
+  .year-count { font-size: 12px; color: var(--ink-4); }
+  .year-body { padding-bottom: var(--space-2); }
+  .month-block + .month-block { margin-top: var(--space-3); }
+  .month-head {
+    display: flex;
+    align-items: baseline;
+    gap: 0.35rem;
+    margin: var(--space-2) 0 var(--space-1);
+    font-size: 12.5px;
+    font-weight: 400;
+    color: var(--ink-4);
+    letter-spacing: 0.04em;
+  }
+  .month-head::before {
+    content: '';
+    width: 7px;
+    height: 7px;
+    border-radius: 2px;
+    background: var(--ink-4);
+  }
+  .month-count { font-size: 11.5px; }
+  @media (prefers-reduced-motion: reduce) {
+    .year-summary::before { transition: none; }
+  }
 </style>

src/components/pages/BooksPage.astro

@@ -28,9 +28,12 @@ const L = {
 
 <BaseLayout track="reading" title={`${L.shelf} · wait4x`} description={locale === 'zh' ? '读过的书与一句策展' : 'Books read, one line each'}>
   <h1 class="page-title">{L.shelf}<span class="count mono">{L.count(books.length)}</span></h1>
-  {years.map((year) => (
-    <section class="year-group">
-      <h2 class="y-label mono">{year}</h2>
+  {years.map((year, yi) => (
+    <details class="year-group" open={yi === 0}>
+      <summary class="y-summary">
+        <span class="y-label mono">{year}</span>
+        <span class="y-count mono">· {books.filter((b) => b.data.pubDate.getFullYear() === year).length} {locale === 'zh' ? '本' : 'books'}</span>
+      </summary>
       <ul class="shelf">
         {books.filter((b) => b.data.pubDate.getFullYear() === year).map((b) => (
           <li>
@@ -62,7 +65,7 @@ const L = {
           </li>
         ))}
       </ul>
-    </section>
+    </details>
   ))}
 </BaseLayout>
 
@@ -75,8 +78,32 @@ const L = {
     gap: var(--space-3);
   }
   .count { font-size: 13px; color: var(--ink-3); }
-  .year-group { margin-top: var(--space-5); }
-  .y-label { font-size: 16px; color: var(--ink-3); margin-bottom: var(--space-3); }
+  .year-group { margin-top: var(--space-4); border-top: 1px solid var(--line); }
+  .y-summary {
+    display: flex;
+    align-items: baseline;
+    gap: 0.4rem;
+    padding: var(--space-2) 0;
+    cursor: pointer;
+    list-style: none;
+  }
+  .y-summary::-webkit-details-marker { display: none; }
+  .y-summary::before {
+    content: '▸';
+    font-size: 11px;
+    color: var(--ink-4);
+    transition: transform var(--dur) var(--ease);
+    transform-origin: 50% 50%;
+    display: inline-block;
+    width: 1em;
+  }
+  .year-group[open] > .y-summary::before { transform: rotate(90deg); }
+  .y-summary:hover .y-label { color: var(--ink-2); }
+  .y-count { font-size: 12px; color: var(--ink-4); }
+  @media (prefers-reduced-motion: reduce) {
+    .y-summary::before { transition: none; }
+  }
+  .y-label { font-size: 16px; color: var(--ink-3); margin-bottom: 0; transition: color var(--dur) var(--ease); }
   .shelf {
     list-style: none;
     padding: 0;