feat(web): keep server duties and PATCH with hydrate ETag

Retain ledger author/reviewer/approver, fail-closed unknown users to
viewer, and send the opened revision ETag instead of a fresh GET.

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

web/src/engine/markdownToBlock.ts

@@ -263,8 +263,12 @@ export function markdownToBlockAST(
     lifecycleState: meta?.lifecycleState || 'drafting',
     isClaimed: meta?.isClaimed ?? false,
     author: meta?.author || '张工',
+    authorId: meta?.authorId,
     reviewer: meta?.reviewer || '李主管',
+    reviewerId: meta?.reviewerId,
     approver: meta?.approver || '王总监',
+    approverId: meta?.approverId,
+    revisionEtag: meta?.revisionEtag,
     summary: meta?.summary || '由项目助手自动生成的受控交付物',
     updatedAt: meta?.updatedAt || new Date().toISOString().replace('T', ' ').substring(0, 16),
     rootBlock,