feat: 内容数据迁移至数据库，合规审查全链路打通

- 文章 HTML 存储从文件系统迁移至 articles 表，删除 releases 目录
- 合规审查从 DB 读取 HTML，审查结果写回 DB，通过后自动推进至待发布
- 新增 todayCount 筛选按钮，与系统概览统计数据一致
- 全屏预览修复：提升 z-index 超过侧边栏，添加退出全屏/关闭按钮
- 统一 '优化' → '审查' 命名，消除前后端术语不一致
- 调度器创作完成后自动触发审查（生成 → 审查 → 待发布）
- 清理旧备份/调试文件、过期大纲和研究笔记

platform/backend/app/api/articles.py

@@ -1,53 +1,42 @@
 from fastapi import APIRouter, HTTPException, Query, Depends
+from sqlalchemy.orm import Session
 from pathlib import Path
 import os
 from datetime import datetime, date
 
 from ..database import get_db
-from ..models import User
+from ..models import User, Article
 from .auth import get_current_user
 
 router = APIRouter(prefix="/api/articles", tags=["articles"])
 
-PROJECT_ROOT = Path('/root/openclaw-workspace/projects/yu-zhi-ran')
-
 @router.get("/drafts")
-def list_drafts(publish_date: str = None, current_user: User = Depends(get_current_user)):
-    """列出指定日期的草稿文件（三平台）"""
-    if not publish_date:
-        publish_date = date.today().isoformat()
-    base_dir = PROJECT_ROOT / "automation" / "data" / "releases" / publish_date
-    if not base_dir.exists():
-        raise HTTPException(status_code=404, detail="No releases for this date")
-    
-    platforms = ["zhihu", "wechat", "xiaohongshu"]
+def list_drafts(topic_id: str = None, current_user: User = Depends(get_current_user), db: Session = Depends(get_db)):
+    """从 articles 表列出草稿"""
+    query = db.query(Article)
+    if topic_id:
+        query = query.filter(Article.topic_id == topic_id)
+    articles = query.order_by(Article.created_at.desc()).all()
     result = {}
-    for p in platforms:
-        path = base_dir / p
-        if path.exists():
-            files = sorted([f.name for f in path.glob("*.html") if f.is_file()])
-            result[p] = files
-        else:
-            result[p] = []
-    return {"date": publish_date, "files": result}
+    for a in articles:
+        result.setdefault(a.platform, []).append({"id": a.id, "topic_id": a.topic_id, "status": a.status})
+    return {"articles": result}
 
 @router.get("/{topic_id}/preview")
-def preview_article(topic_id: str, platform: str = "zhihu", publish_date: str = None, current_user: User = Depends(get_current_user)):
-    """预览某选题的HTML内容"""
-    if not publish_date:
-        publish_date = date.today().isoformat()
-    filename = f"{platform}_{topic_id}_{platform}.html"
-    file_path = PROJECT_ROOT / "automation" / "data" / "releases" / publish_date / platform / filename
-    if not file_path.exists():
-        raise HTTPException(status_code=404, detail=f"Article not found: {file_path}")
-    content = file_path.read_text(encoding='utf-8')
-    return {"topic_id": topic_id, "platform": platform, "html": content}
+def preview_article(topic_id: str, platform: str = "zhihu", current_user: User = Depends(get_current_user), db: Session = Depends(get_db)):
+    """从 articles 表预览某选题的 HTML 内容"""
+    article_id = f"{platform}_{topic_id}"
+    article = db.query(Article).filter(Article.id == article_id).first()
+    if not article or not article.html_content:
+        raise HTTPException(status_code=404, detail=f"Article not found for {topic_id} on {platform}")
+    return {"topic_id": topic_id, "platform": platform, "html": article.html_content}
 
 @router.get("/optimization-report")
 def get_optimization_report(publish_date: str = None, current_user: User = Depends(get_current_user)):
     """获取合规优化报告"""
     if not publish_date:
         publish_date = date.today().isoformat()
+    PROJECT_ROOT = Path('/root/openclaw-workspace/projects/yu-zhi-ran')
     report_path = PROJECT_ROOT / "automation" / "data" / "drafts" / publish_date / "optimization_report.json"
     if not report_path.exists():
         raise HTTPException(status_code=404, detail="No optimization report for this date")