feat(MCN工作台): 数据功能页+图标扁平化+多项UI优化

- 工作台大版本升级：hash 路由 + 6 数据功能页（周榜/热门账号/账号详情/视频详情/AI写脚本/AI写作复盘），只读复用 dsh 库副本 + 抖音榜单 JSON
- 数据库隔离：复制 dsh 库到 mcn-work-shop/，与 dsh 原库各访问各的（已 gitignore）
- 图标全面扁平化：Lucide 线性 SVG，功能图标亮色区分，文字标题去图标
- 首页重构：功能入口卡 + AI写剧本快捷卡片(2列/8个/5行预览) + 独立帮助页 + header 精简
- 新增设计技能 impeccable + taste-skill（生成网页时参考）
- 修复：fmtTime 跨 script 全局冲突(P0)、弹窗关闭、外链新标签打开等

.workbuddy/skills/impeccable/scripts/surface-brief.mjs

@@ -0,0 +1,74 @@
+#!/usr/bin/env node
+import fs from 'node:fs';
+import path from 'node:path';
+import { fileURLToPath, pathToFileURL } from 'node:url';
+import { resolveProjectRoot } from './context.mjs';
+import {
+  listSurfaceBriefs,
+  resolveSurfaceBrief,
+  surfaceBriefPathForTarget,
+  writeSurfaceBrief,
+} from './lib/surface-briefs.mjs';
+
+function summary(brief, projectRoot) {
+  return {
+    slug: brief.slug,
+    path: path.relative(projectRoot, brief.path).split(path.sep).join('/'),
+    primaryTarget: brief.primaryTarget,
+    relatedTargets: brief.relatedTargets,
+  };
+}
+
+function main(argv) {
+  const [command, target, bodyFile, ...relatedTargets] = argv;
+  const projectRoot = resolveProjectRoot(process.cwd(), target ? { targetPath: target } : {});
+  if (command === 'path') {
+    const filePath = surfaceBriefPathForTarget(target, { projectRoot });
+    if (!filePath) throw new Error('surface brief path requires a concrete target');
+    process.stdout.write(`${path.relative(process.cwd(), filePath) || filePath}\n`);
+    return;
+  }
+  if (command === 'list') {
+    process.stdout.write(`${JSON.stringify(listSurfaceBriefs(projectRoot).map((brief) => summary(brief, projectRoot)), null, 2)}\n`);
+    return;
+  }
+  if (command === 'read') {
+    const result = resolveSurfaceBrief(projectRoot, target || null);
+    if (result.brief) {
+      process.stdout.write(result.brief.text);
+      return;
+    }
+    if (result.candidates.length) process.stderr.write(`${JSON.stringify(result.candidates.map((brief) => summary(brief, projectRoot)), null, 2)}\n`);
+    process.exit(2);
+  }
+  if (command === 'write') {
+    if (!target || !bodyFile) throw new Error('usage: surface-brief.mjs write <primary-target> <body-file>');
+    const filePath = writeSurfaceBrief({
+      projectRoot,
+      primaryTarget: target,
+      relatedTargets,
+      body: fs.readFileSync(bodyFile, 'utf-8'),
+    });
+    process.stdout.write(`${path.relative(process.cwd(), filePath) || filePath}\n`);
+    return;
+  }
+  throw new Error('usage: surface-brief.mjs <path|list|read|write> [target] [body-file] [related-target ...]');
+}
+
+function isMainModule() {
+  if (!process.argv[1]) return false;
+  try {
+    return fs.realpathSync(fileURLToPath(import.meta.url)) === fs.realpathSync(process.argv[1]);
+  } catch {
+    return import.meta.url === pathToFileURL(process.argv[1]).href;
+  }
+}
+
+if (isMainModule()) {
+  try {
+    main(process.argv.slice(2));
+  } catch (error) {
+    process.stderr.write(`${error?.message || error}\n`);
+    process.exit(1);
+  }
+}