feat: 评论/帖子编辑历史与编辑标记，内容锁定

- 新增 smartDiff 差异计算与 EditHistoryModal 编辑历史弹窗，替换原 CommentEditHistoryModal
- 新增 PostEditedMark 编辑标记展示
- 新增内容锁定机制（content_lock）防止并发编辑冲突
- 审核与通知服务适配

frontend/app/admin/announcements/AnnouncementComposeClient.tsx

@@ -21,6 +21,9 @@ import { ANNOUNCEMENT_COLORS, announcementPublicPath } from "./announcementColor
 type PublishKey = "published" | "draft";
 type StatusFilter = "all" | "published" | "draft";
 
+/** 公告正文字符上限（与后端 service/announcement.go 校验一致） */
+const CONTENT_MAX = 20000;
+
 type FormState = {
   title: string;
   content: string;
@@ -328,8 +331,9 @@ export default function AnnouncementComposeClient({
               value={form.content}
               onChange={(content) => {
                 setErrors((prev) => ({ ...prev, content: undefined }));
-                patchForm({ content });
+                patchForm({ content: content.slice(0, CONTENT_MAX) });
               }}
+              maxChars={CONTENT_MAX}
               allowHide
               allowReplyHide={false}
               placeholder="请输入公告正文，支持 Markdown…"

frontend/app/admin/badges/BadgesClient.tsx

@@ -200,7 +200,7 @@ export default function BadgesClient() {
             管理员自定义徽章：全站作者处展示前 2 枚，个人主页展示徽章墙；授予后用户会收到站内通知。
           </p>
         </div>
-        <button type="button" className="btn btn-solid btn-sm" onClick={openCreate}>
+        <button type="button" className="btn btn-primary btn-sm" onClick={openCreate}>
           <Plus size={14} /> 新建徽章
         </button>
       </div>
@@ -290,7 +290,7 @@ export default function BadgesClient() {
                   ) : (
                     <button
                       type="button"
-                      className="btn btn-solid btn-sm"
+                      className="btn btn-primary btn-sm"
                       disabled={grantingId === u.id}
                       onClick={() => void grant(u.id)}
                     >
@@ -416,7 +416,7 @@ export default function BadgesClient() {
           </button>
           <button
             type="button"
-            className="btn btn-solid btn-sm"
+            className="btn btn-primary btn-sm"
             disabled={saving || runeCount(form.name.trim()) === 0}
             onClick={() => void saveForm()}
           >

frontend/app/admin/content/ContentAdmin.tsx

@@ -25,6 +25,7 @@ import {
   apiAdminContentPosts,
   apiAdminContentComments,
   apiAdminSoftDeletePost,
+  apiCommentHistory,
   apiAdminRestorePost,
   apiAdminPurgePost,
   apiAdminSoftDeleteComment,
@@ -48,7 +49,7 @@ import AutolinkText from "@/components/AutolinkText";
 import ConfirmDialog from "@/components/ConfirmDialog";
 import StaffDeletePostModal from "@/components/StaffDeletePostModal";
 import DeleteCommentModal from "@/components/DeleteCommentModal";
-import CommentEditHistoryModal from "@/components/CommentEditHistoryModal";
+import EditHistoryModal from "@/components/EditHistoryModal";
 import {
   AdminEmpty,
   AdminPageHeader,
@@ -320,6 +321,7 @@ export default function ContentAdmin({
   const [staffDeleteComment, setStaffDeleteComment] = useState<AdminContentComment | null>(null);
   const [staffDeleteCommentBusy, setStaffDeleteCommentBusy] = useState(false);
   const [historyCommentId, setHistoryCommentId] = useState<number | null>(null);
+  const [historyCommentContent, setHistoryCommentContent] = useState("");
 
   const refreshCounts = useCallback(() => {
     apiAdminContentCounts().then(setCounts).catch(() => {});
@@ -710,11 +712,17 @@ export default function ContentAdmin({
                       onReject={() => askReject("comments", c.id)}
                     />
                   ) : null}
-                  <ContentAction
-                    label="历史"
-                    icon={<History size={13} />}
-                    onClick={() => setHistoryCommentId(c.id)}
-                  />
+                  {/* 未编辑（无修订快照）的评论不展示历史入口，避免打开空记录 */}
+                  {c.edited ? (
+                    <ContentAction
+                      label="历史"
+                      icon={<History size={13} />}
+                      onClick={() => {
+                        setHistoryCommentContent(c.content);
+                        setHistoryCommentId(c.id);
+                      }}
+                    />
+                  ) : null}
                   {c.deleted ? (
                     <>
                       {canModerateAuthor({ role: viewerRole }, c.user?.role) ? (
@@ -930,9 +938,14 @@ export default function ContentAdmin({
         }}
       />
 
-      <CommentEditHistoryModal
+      <EditHistoryModal
         open={historyCommentId != null}
-        commentId={historyCommentId}
+        title="评论编辑历史"
+        currentContent={historyCommentContent}
+        fetchPage={(p, s) => {
+          if (historyCommentId == null) return Promise.reject(new Error("未选择评论"));
+          return apiCommentHistory(historyCommentId, p, s);
+        }}
         onClose={() => setHistoryCommentId(null)}
       />
     </div>

frontend/app/admin/pages/PageComposeClient.tsx

@@ -20,6 +20,9 @@ import useUnsavedGuard from "@/hooks/useUnsavedGuard";
 type PublishKey = "published" | "draft";
 type StatusFilter = "all" | "published" | "draft";
 
+/** 单页正文字符上限（与后端 service/site_page.go 校验一致） */
+const CONTENT_MAX = 20000;
+
 type FormState = {
   slug: string;
   title: string;
@@ -365,8 +368,9 @@ export default function PageComposeClient({
               value={form.content}
               onChange={(content) => {
                 setErrors((prev) => ({ ...prev, content: undefined }));
-                patchForm({ content });
+                patchForm({ content: content.slice(0, CONTENT_MAX) });
               }}
+              maxChars={CONTENT_MAX}
               allowHide={false}
               placeholder="请输入页面正文，支持 Markdown…"
               rows={16}

frontend/app/admin/points/PointsTabs.tsx

@@ -56,7 +56,7 @@ export default function PointsTabs({
     : TAB_OPTIONS.filter((o) => o.key === "overview");
 
   return (
-    <div>
+    <div className={tab === "users" ? "admin-points-users-tab" : undefined}>
       {canManage ? (
         <div className="mb-4">
           <AdminSegmented

frontend/app/admin/points/UserPointsTab.tsx

@@ -24,6 +24,15 @@ const fmt = (n?: number) => (Number(n) || 0).toLocaleString("zh-CN");
 
 type PointsSortKey = "id" | "points" | "total_points";
 
+/**
+ * 表头吸顶样式：sticky 相对 .admin-canvas 滚动口生效（lg 起外层不再是滚动容器，见下方包装层）。
+ * 分隔线用 inset 阴影而非 border——border-collapse: collapse 下吸顶 th 的边线会丢失。
+ */
+const thStickStyle = {
+  background: "var(--panel)",
+  boxShadow: "inset 0 -1px 0 var(--line)",
+} as const;
+
 /** 表头排序按钮：未激活显示双向箭头，激活显示单向箭头并高亮 */
 function SortHeader({
   label,
@@ -158,24 +167,40 @@ export default function UserPointsTab() {
         />
       </div>
 
-      <div className="panel p-0 overflow-hidden">
-        <div className="overflow-x-auto">
+      <div className="panel p-0">
+        {/* lg 起放开横向滚动容器：sticky th 才能相对 admin-canvas 吸顶；窄屏保留横向滚动（不吸顶） */}
+        <div className="overflow-x-auto lg:overflow-x-visible">
           <table className="w-full text-[13px]" style={{ borderCollapse: "collapse" }}>
             <thead>
-              <tr style={{ borderBottom: "1px solid var(--line)" }}>
-                <th className="px-4 py-2.5 text-left font-medium" style={{ color: "var(--ink-3)" }}>
+              <tr>
+                <th
+                  className="sticky top-0 z-10 px-4 py-2.5 text-left font-medium"
+                  style={{ color: "var(--ink-3)", ...thStickStyle }}
+                >
                   用户
                 </th>
-                <th className="px-4 py-2.5 text-right font-medium" style={{ color: "var(--ink-3)" }}>
+                <th
+                  className="sticky top-0 z-10 px-4 py-2.5 text-right font-medium"
+                  style={{ color: "var(--ink-3)", ...thStickStyle }}
+                >
                   <SortHeader label="余额" active={sort === "points"} dir={dir} onClick={() => toggleSort("points")} />
                 </th>
-                <th className="px-4 py-2.5 text-right font-medium" style={{ color: "var(--ink-3)" }}>
+                <th
+                  className="sticky top-0 z-10 px-4 py-2.5 text-right font-medium"
+                  style={{ color: "var(--ink-3)", ...thStickStyle }}
+                >
                   <SortHeader label="累计获得" active={sort === "total_points"} dir={dir} onClick={() => toggleSort("total_points")} />
                 </th>
-                <th className="px-4 py-2.5 text-left font-medium" style={{ color: "var(--ink-3)" }}>
+                <th
+                  className="sticky top-0 z-10 px-4 py-2.5 text-left font-medium"
+                  style={{ color: "var(--ink-3)", ...thStickStyle }}
+                >
                   等级
                 </th>
-                <th className="px-4 py-2.5 text-right font-medium" style={{ color: "var(--ink-3)" }}>
+                <th
+                  className="sticky top-0 z-10 px-4 py-2.5 text-right font-medium"
+                  style={{ color: "var(--ink-3)", ...thStickStyle }}
+                >
                   操作
                 </th>
               </tr>

frontend/app/admin/settings/AccessSettings.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { ExternalLink, LogIn, MessageSquare, MessagesSquare, ShieldCheck, ShieldOff, Timer } from "lucide-react";
+import { ExternalLink, LogIn, MessageSquare, MessagesSquare, ShieldCheck, ShieldOff, Timer, Lock, Hourglass, Coins, History } from "lucide-react";
 import { useState } from "react";
 import {
   AdminSettingsGroup,
@@ -18,6 +18,59 @@ function InstantNote({ saving }: { saving?: boolean }) {
   return <span className="admin-settings-instant">{saving ? "正在保存…" : "修改后立即生效"}</span>;
 }
 
+/** 内容锁定 4 键（小时上限 8760 / 积分上限 100，后端裁剪） */
+type LockKeys = Pick<
+  PublicSettings,
+  "post_edit_lock_hours" | "comment_edit_lock_hours" | "necro_reply_after_hours" | "necro_reply_penalty"
+>;
+type LockKey = keyof LockKeys;
+
+const LOCK_META: { key: LockKey; icon: React.ReactNode; label: string; hint: string; max: number; unit: string; toast: (v: number) => string }[] = [
+  {
+    key: "post_edit_lock_hours",
+    icon: <Lock size={15} />,
+    label: "帖子可编辑时长",
+    hint: "发帖后仅在该时长内可编辑（0=不限制，上限 8760 小时），到期后编辑入口隐藏；管理团队不受限。",
+    max: 8760,
+    unit: "小时",
+    toast: (v) => (v === 0 ? "已关闭帖子编辑时限" : `帖子可编辑时长已设为 ${v} 小时`),
+  },
+  {
+    key: "comment_edit_lock_hours",
+    icon: <Hourglass size={15} />,
+    label: "评论可编辑时长",
+    hint: "评论发布后仅在该时长内可编辑（0=不限制，上限 8760 小时）；管理团队不受限。",
+    max: 8760,
+    unit: "小时",
+    toast: (v) => (v === 0 ? "已关闭评论编辑时限" : `评论可编辑时长已设为 ${v} 小时`),
+  },
+  {
+    key: "necro_reply_after_hours",
+    icon: <History size={15} />,
+    label: "旧帖回复判定时长",
+    hint: "回复超过该时长的帖子将提醒作者并按下方分值扣分（0=关闭，上限 8760 小时）；管理团队不受限。",
+    max: 8760,
+    unit: "小时",
+    toast: (v) => (v === 0 ? "已关闭旧帖回复提醒" : `旧帖判定时长已设为 ${v} 小时`),
+  },
+  {
+    key: "necro_reply_penalty",
+    icon: <Coins size={15} />,
+    label: "旧帖回复扣除积分",
+    hint: "触发旧帖回复时扣除的积分（0=仅提醒不扣分，上限 100）；积分不足将无法回复。",
+    max: 100,
+    unit: "分",
+    toast: (v) => (v === 0 ? "旧帖回复仅提醒不扣分" : `旧帖回复将扣除 ${v} 积分`),
+  },
+];
+
+const pickLock = (s: PublicSettings): LockKeys => ({
+  post_edit_lock_hours: s.post_edit_lock_hours,
+  comment_edit_lock_hours: s.comment_edit_lock_hours,
+  necro_reply_after_hours: s.necro_reply_after_hours,
+  necro_reply_penalty: s.necro_reply_penalty,
+});
+
 /** 内容互动开关 + 访问安全模块 */
 export default function AccessSettings({ initial }: { initial: PublicSettings }) {
   const [allowComments, setAllowComments] = useState(initial.allow_comments !== false);
@@ -37,8 +90,12 @@ export default function AccessSettings({ initial }: { initial: PublicSettings })
   const [togglingTrust, setTogglingTrust] = useState(false);
   const [togglingWithoutReview, setTogglingWithoutReview] = useState(false);
   const [savingCooldown, setSavingCooldown] = useState(false);
+  const [lockForm, setLockForm] = useState<LockKeys>(() => pickLock(initial));
+  const [savedLock, setSavedLock] = useState<LockKeys>(() => pickLock(initial));
+  const [savingLockKey, setSavingLockKey] = useState<LockKey | null>(null);
   const [moduleDirty, setModuleDirty] = useState(false);
-  const leave = useUnsavedGuard(moduleDirty);
+  const lockDirty = (Object.keys(savedLock) as LockKey[]).some((k) => lockForm[k] !== savedLock[k]);
+  const leave = useUnsavedGuard(moduleDirty || lockDirty);
 
   const toggleComments = async () => {
     if (togglingComments) return;
@@ -164,6 +221,23 @@ export default function AccessSettings({ initial }: { initial: PublicSettings })
     }
   };
 
+  const saveLock = async (key: LockKey) => {
+    if (savingLockKey) return;
+    const n = Math.max(0, Math.min(8760, Math.round(Number(lockForm[key])) || 0));
+    setSavingLockKey(key);
+    try {
+      const res = await apiUpdateSiteSettings({ [key]: n });
+      const saved = pickLock(res);
+      setLockForm((f) => ({ ...f, [key]: saved[key] }));
+      setSavedLock((f) => ({ ...f, [key]: saved[key] }));
+      toast(LOCK_META.find((m) => m.key === key)?.toast(saved[key]) || "已保存", "ok");
+    } catch (e) {
+      toast(e instanceof Error ? e.message : "保存失败");
+    } finally {
+      setSavingLockKey(null);
+    }
+  };
+
   return (
     <div className="admin-settings-stack">
       <AdminSettingsGroup title="内容与互动">
@@ -308,6 +382,31 @@ export default function AccessSettings({ initial }: { initial: PublicSettings })
           </div>
         </AdminSettingsRow>
       </AdminSettingsGroup>
+      <AdminSettingsGroup title="内容锁定与旧帖回复">
+        {LOCK_META.map((m) => (
+          <AdminSettingsRow key={m.key} label={<span className="inline-flex items-center gap-1.5">{m.icon} {m.label}</span>} hintBelow={m.hint}>
+            <div className="flex items-center gap-2 flex-wrap">
+              <AdminStepper
+                value={lockForm[m.key]}
+                onChange={(v) => setLockForm((f) => ({ ...f, [m.key]: v }))}
+                min={0}
+                max={m.max}
+                unit={m.unit}
+                ariaLabel={`${m.label}${m.unit}`}
+                disabled={savingLockKey !== null}
+              />
+              <button
+                type="button"
+                className="btn btn-line btn-sm"
+                disabled={savingLockKey !== null || lockForm[m.key] === savedLock[m.key]}
+                onClick={() => void saveLock(m.key)}
+              >
+                {savingLockKey === m.key ? "保存中…" : "保存"}
+              </button>
+            </div>
+          </AdminSettingsRow>
+        ))}
+      </AdminSettingsGroup>
       <OperationsPanel name="security" onDirtyChange={setModuleDirty} />
       <ConfirmDialog
         open={leave.leaveOpen}

frontend/app/admin/settings/EconomySettings.tsx

@@ -212,7 +212,7 @@ export default function EconomySettings({ initial }: { initial: PublicSettings }
       <div className="flex items-center gap-3">
         <button
           type="button"
-          className="btn btn-solid btn-sm"
+          className="btn btn-primary btn-sm"
           disabled={saving || !dirty}
           onClick={() => void save()}
         >