feat(mindspace): 全部页面管理、级联删除与页面同步去重

支持全部页面分页/多选/删除/分享，删除时可选移除广场帖并清理工作区附件；修复并发同步重复创建页面，并补齐预览下载链接重写与 iframe 下载权限。

Co-authored-by: Cursor <cursoragent@cursor.com>

mindspace-pages.test.mjs

@@ -63,6 +63,17 @@ test('renderPublicationHtml serves html pages without escaping markup', () => {
   assert.doesNotMatch(html, /MINDSPACE/);
 });
 
+test('normalizeListPageFilters clamps limit and offset', () => {
+  assert.deepEqual(pageInternals.normalizeListPageFilters({ limit: 999, offset: -5 }), {
+    limit: 100,
+    offset: 0,
+  });
+  assert.deepEqual(pageInternals.normalizeListPageFilters({ limit: 15, offset: 30 }), {
+    limit: 15,
+    offset: 30,
+  });
+});
+
 test('preview rendering escapes active HTML and emits a restrictive CSP', () => {
   const html = pageInternals.renderPreviewHtml({
     title: '<script>alert(1)</script>',
@@ -94,6 +105,7 @@ test('buildPageDeleteSummary lists cascade delete impact', () => {
     page: { title: '麻婆豆腐', versionCount: 2 },
     onlinePublication: { publicUrl: '/u/john/pages/mapo' },
     offlinePublicationCount: 1,
+    plazaPosts: [{ id: 'post-1', title: '广场帖', status: 'published', publicationId: 'pub-1' }],
     linkedAssets: [{ id: 'a1' }, { id: 'a2' }],
     linkedAssetBytes: 2048,
     linkedAgentJobCount: 1,
@@ -101,5 +113,6 @@ test('buildPageDeleteSummary lists cascade delete impact', () => {
   });
   assert.match(lines[0], /麻婆豆腐/);
   assert.ok(lines.some((line) => line.includes('在线公开链接')));
+  assert.ok(lines.some((line) => line.includes('广场')));
   assert.ok(lines.some((line) => line.includes('原始上传资料不会被删除')));
 });