feat: 专家库显示服务联系状态,未联系需先建立才能咨询

- 后端 /experts 返回 connected 字段(基于 expert_consultations 表)
- 前端卡片显示"已联系"徽章
- 未联系时按钮为"建立联系",调用 selectExpert API
- 已联系后按钮变为"咨询",可跳转对应场景

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

api.py

@@ -1282,9 +1282,32 @@ class RatingRequest(BaseModel):
 
 
 @app.get("/experts")
-def list_experts(category: str | None = None):
-    """列出专家,支持按分类筛选(legal/decision/emotion/life)。"""
-    return {"results": expert_store.list_experts(category=category, status="active")}
+def list_experts(category: str | None = None, authorization: str | None = Header(default=None)):
+    """列出专家,支持按分类筛选(legal/decision/emotion/life)。
+    登录后额外返回 connected 字段(是否已建立服务联系)。
+    """
+    results = expert_store.list_experts(category=category, status="active")
+    # 查询当前用户已建立联系的专家ID集合
+    phone = get_current_phone(authorization)
+    if phone and results:
+        conn = _matter_dsn()
+        try:
+            cur = conn.cursor()
+            expert_ids = [r["id"] for r in results]
+            cur.execute(
+                "SELECT DISTINCT expert_id FROM expert_consultations "
+                "WHERE user_phone = %s AND expert_id = ANY(%s)",
+                (phone, expert_ids),
+            )
+            connected_ids = {r[0] for r in cur.fetchall()}
+            for r in results:
+                r["connected"] = r["id"] in connected_ids
+        finally:
+            conn.close()
+    else:
+        for r in results:
+            r["connected"] = False
+    return {"results": results}
 
 
 @app.get("/experts/{expert_id}")