fix: 三平台内容差异化 + admin敏感词管理表格化

- writer.py: _expand_section() 去除 <100字阈值，始终调用 LLM 平台专属扩写
- prompt_loader.py: 新增 section_expansion_zhihu/wechat/xiaohongshu 三个独立 prompt
- admin.html: 配置管理标签页 + 敏感词/清理规则子标签 + 敏感词表格化管理(编辑/删除)
- config_items.py: PUT /sensitive-words/{id} 支持更新 word/category
- compliance_checker.py: AI 套话从 DB 加载 + 人称规则修正
- initial_data.py: PlatformConfig 字数迁移 + 新种子
- 各前端页面: LLM 配置 rate_limit 字段 + 供应商列表排序

scripts/writer.py

@@ -43,9 +43,9 @@ logger = logging.getLogger(__name__)
 _md_parser = mistune.create_markdown()
 
 _FALLBACK_PLATFORM_CONFIG = {
-    "zhihu": {"max_chars": 3000, "style": "深度长文分析", "min_chars": 1500},
-    "wechat": {"max_chars": 1500, "style": "亲切口语化", "min_chars": 800},
-    "xiaohongshu": {"max_chars": 800, "style": "图文笔记，emoji+标签", "min_chars": 300},
+    "zhihu": {"max_chars": 8000, "style": "深度长文分析", "min_chars": 3000},
+    "wechat": {"max_chars": 4000, "style": "个人叙事对话感", "min_chars": 2000},
+    "xiaohongshu": {"max_chars": 1000, "style": "图文笔记，精炼实用", "min_chars": 400},
 }
 
 def _load_platform_config() -> dict:
@@ -144,28 +144,30 @@ class Writer:
         bullet_count = sum(1 for l in lines if l.startswith(('- ', '* ', '**', '+ ')))
         return bullet_count / len(lines) > 0.4
 
-    def _expand_section(self, section: Dict) -> str:
+    def _expand_section(self, section: Dict, platform: str = "zhihu") -> str:
         content = section.get('content', '').strip()
-        # 大纲要点格式（>40% 行以 -/*/** 开头）或内容过短（<100字）应由 LLM 展开为连贯段落
-        if HAVE_LLM and (self._is_bullet_only(content) or (content and len(content) < 100)):
-            logger.info(f"使用 LLM 扩写章节(要点→段落): {section['title']}")
-            prompt = get_prompt("section_expansion",
+        platform_prompt_key = f"section_expansion_{platform}"
+        if platform not in ("zhihu", "wechat", "xiaohongshu"):
+            platform_prompt_key = "section_expansion_zhihu"
+
+        if HAVE_LLM and content:
+            logger.info(f"LLM 扩写 [{platform}]: {section['title']} ({len(content)} chars)")
+            prompt = get_prompt(platform_prompt_key,
                 topic_title=self.topic['title'],
                 section_title=section['title'],
                 date=datetime.datetime.now().strftime('%Y年%m月%d日'),
                 content=content,
             )
             try:
-                params = get_prompt_params("section_expansion")
+                params = get_prompt_params(platform_prompt_key) or {"temperature": 0.75, "max_tokens": 3000}
                 expanded = call_llm(prompt, temperature=params.get("temperature", 0.75), max_tokens=params.get("max_tokens", 3000))
                 if expanded:
                     cleaned = self._clean_markdown(expanded.strip())
                     if cleaned:
                         return cleaned
             except Exception as e:
-                logger.warning(f"LLM 扩写失败: {e}")
+                logger.warning(f"LLM 扩写失败 [{platform}]: {e}")
 
-        # Fallback: 将 bullet points 展开为段落（过滤噪音行）
         lines = [l.strip() for l in content.split('\n') if not self._is_outline_noise(l)]
         if lines:
             sentences = []
@@ -185,17 +187,16 @@ class Writer:
                 return self._clean_markdown(result)
         return ''
 
-    def generate_full_markdown(self) -> str:
+    def generate_platform_markdown(self, platform: str = "zhihu") -> str:
         sections = self._parse_outline_sections()
         parts = []
         for sec in sections:
             if sec['level'] == 1:
                 if sec.get('content'):
-                    expanded = self._expand_section(sec)
+                    expanded = self._expand_section(sec, platform)
                     if expanded:
                         parts.append(expanded + "\n")
                 continue
-            # 跳过大纲结构噪音节点
             title_stripped = sec['title'].strip()
             if title_stripped in ('文章大纲', '大纲', '文章结构', '结构'):
                 continue
@@ -204,7 +205,7 @@ class Writer:
             heading = f"{'#' * sec['level']} {sec['title']}"
             parts.append(heading)
             if sec.get('content'):
-                expanded = self._expand_section(sec)
+                expanded = self._expand_section(sec, platform)
                 parts.append(expanded + "\n")
         full_md = "\n".join(parts).strip()
         # 收集所有引用来源，统一添加到文末
@@ -286,8 +287,6 @@ class Writer:
         if platform == "wechat":
             result = []
             for line in lines:
-                # 人称统一：我们→我，你们→你
-                line = line.replace('我们', '我').replace('你们', '你').replace('我', '你')
                 if line.startswith('### '):
                     result.append(f"\n**{line[4:]}**\n")
                 elif line.startswith('## '):
@@ -370,6 +369,7 @@ class Writer:
             prompt = get_prompt("title_optimize_wechat",
                 title=original,
                 core=self.topic.get('core_concept', ''),
+                field=self.topic.get('field', ''),
             )
         elif platform == "xiaohongshu":
             prompt = get_prompt("title_optimize_xhs",
@@ -459,10 +459,10 @@ class Writer:
         logger.info(f"选题 {self.topic_id} 状态已更新为待审查（数据库）")
 
     def run(self):
-        logger.info("开始撰写阶段")
-        markdown = self.generate_full_markdown()
+        logger.info("开始撰写阶段（三平台独立展开）")
         results = {}
         for platform in ["zhihu", "wechat", "xiaohongshu"]:
+            markdown = self.generate_platform_markdown(platform)
             html = self.generate_platform_html(markdown, platform)
             results[platform] = str(self.save_html(html, platform))
         self.mark_draft()