feat(M6): 第2环标杆8维分析引擎

8维草案(banana不变量+俊达配方+3链接):标题公式/开头钩子/正文结构/
卖点呈现/情绪语气emoji/目标人群/话题标签/视觉配图节奏。
- _benchmark_prompt.py: 8维vision prompt(不打分,提炼可复用配方)
- benchmark_analyzer.py: 引擎核心(vision读截图+手填亮点→8维JSON,失败兜底)
- benchmarks.py: POST /benchmarks/{id}/analyze 端点(写features_json,流转analyze_status)
端到端实测:8维齐全0缺失,真调LLM(conf0.9非兜底),落库done,质量高(识别收藏钩子/成分背书/诚实标未体现)

backend/app/api/v1/benchmarks.py

@@ -33,10 +33,18 @@ class BannedWordCreate(BaseModel):
 
 
 def _fmt_benchmark(b: BenchmarkNote) -> dict:
+    import json
+    features = None
+    if b.features_json:
+        try:
+            features = json.loads(b.features_json)
+        except Exception:
+            features = None
     return {
         "id": b.id, "product_id": b.product_id,
         "screenshot_url": b.screenshot_url,
         "highlights": b.highlights, "link_url": b.link_url,
+        "features": features, "analyze_status": b.analyze_status,
         "created_at": b.created_at.isoformat(),
     }
 
@@ -84,7 +92,66 @@ def create_benchmark(
     return ok(_fmt_benchmark(b))
 
 
-# ── 违禁词库 ────────────────────────────────────────────────
+@router.post("/benchmarks/{benchmark_id}/analyze")
+async def analyze_benchmark_note(
+    benchmark_id: int,
+    current_user: Annotated[CurrentUser, Depends(require_admin)] = None,
+    db: Session = Depends(get_db),
+):
+    """
+    第2环：对已存标杆笔记跑 8 维拆解。
+    输入源=screenshot_url 截图(vision) + highlights 手填亮点(参考)。
+    结果写入 features_json，analyze_status 流转 analyzing→done/failed。
+    key 链路遵基石B：plain_key 只活局部，立即清零。
+    """
+    import json
+    from app.core.response import raise_business
+    from app.models.workspace import UserApiKey
+    from app.utils.fernet_utils import decrypt_key
+    from app.services.ai_engine.gemini_factory import build_ai_clients
+    from app.services.ai_engine.benchmark_analyzer import analyze_benchmark
+
+    b = db.query(BenchmarkNote).filter(
+        BenchmarkNote.id == benchmark_id,
+        BenchmarkNote.workspace_id == current_user.workspace_id,
+    ).first()
+    if not b:
+        raise_not_found("标杆笔记不存在")
+    if not b.screenshot_url and not b.highlights:
+        raise_business("该标杆无截图也无手填亮点，无法分析")
+
+    # 读截图字节（screenshot_url 存的是上传后的绝对/相对路径）
+    screenshot = None
+    if b.screenshot_url:
+        try:
+            with open(b.screenshot_url, "rb") as f:
+                screenshot = f.read()
+        except Exception as e:
+            logger.warning("标杆截图读取失败 id=%s: %s", benchmark_id, e)
+
+    api_key_row = db.query(UserApiKey).filter(
+        UserApiKey.user_id == current_user.user_id,
+        UserApiKey.workspace_id == current_user.workspace_id,
+        UserApiKey.provider.in_(["openai", "apiports"]),
+    ).first()
+    if not api_key_row:
+        raise_business("未配置 API Key，请先在设置中录入")
+    plain_key = decrypt_key(api_key_row.encrypted_key)
+    clients = build_ai_clients(plain_key)
+    plain_key = None
+
+    b.analyze_status = "analyzing"; db.commit()
+    try:
+        result = await analyze_benchmark(clients, screenshot, b.highlights)
+    finally:
+        await clients.aclose()
+
+    b.features_json = json.dumps(result, ensure_ascii=False)
+    b.analyze_status = "done" if result.get("source") != "fallback" else "failed"
+    db.commit(); db.refresh(b)
+    logger.info("benchmark analyzed id=%s status=%s source=%s",
+                benchmark_id, b.analyze_status, result.get("source"))
+    return ok({**_fmt_benchmark(b), "features": result, "analyze_status": b.analyze_status})
 @router.get("/banned-words")
 def list_banned_words(
     page: int = 1, page_size: int = 50,