fix(auth): 审批人列表按公司收窄——本公司主管 + 所有超管

- get_approvers：普通/主管仅见 department=本人公司 的 SUPERVISOR 与全部 SUPER_ADMIN；超管本人不受限

inventory-backend/app/api/v1/auth.py

@@ -339,11 +339,25 @@ def get_approvers():
         from app.models.system import SysUser
 
         current_user_id = get_jwt_identity()
+        me = SysUser.query.get(current_user_id) if current_user_id else None
 
-        users = SysUser.query.filter(
-            SysUser.role.in_(['SUPER_ADMIN', 'SUPERVISOR']),
-            SysUser.status == 'active'
-        ).all()
+        from sqlalchemy import and_, or_
+        if me and (me.role or '').upper() == 'SUPER_ADMIN':
+            # 超管本人：不受部门限制，仍列出全部主管+超管
+            users = SysUser.query.filter(
+                SysUser.role.in_(['SUPER_ADMIN', 'SUPERVISOR']),
+                SysUser.status == 'active'
+            ).all()
+        else:
+            # 普通/主管：只列“本公司(department)主管” + “所有超管”
+            my_company = me.department if me else None
+            users = SysUser.query.filter(
+                SysUser.status == 'active',
+                or_(
+                    SysUser.role == 'SUPER_ADMIN',
+                    and_(SysUser.role == 'SUPERVISOR', SysUser.department == my_company)
+                )
+            ).all()
 
         return jsonify({
             'msg': '获取成功',