feat: Add role code to system_role.json and update system_users.json creator_id to null

fix: Refactor initialize.py to handle nested children data during initialization

feat: Implement tree structure traversal functions in common_util.py

chore: Update requirements.txt to specify sqlalchemy-crud-plus version and add rich

refactor: Change API endpoints in dept.ts and menu.ts to return tree structure

feat: Add code field to role, dept, and menu interfaces in respective TypeScript files

fix: Update dept and role Vue components to display and handle code field

docs: Add comprehensive project documentation for FastAPI Vue3 Admin

backend/app/utils/common_util.py

@@ -126,6 +126,62 @@ def get_child_recursion(
         get_child_recursion(child, id_map, ids)
     return ids
 
+
+def traversal_to_tree(nodes: list[dict[str, Any]]) -> list[dict[str, Any]]:
+    """
+    通过遍历算法构造树形结构
+
+    :param nodes: 树节点列表
+    :return:
+    """
+    tree: list[dict[str, Any]] = []
+    node_dict = {node['id']: node for node in nodes}
+
+    for node in nodes:
+        # 确保每个节点都有children字段，即使没有子节点也设置为null
+        if 'children' not in node:
+            node['children'] = None
+            
+        parent_id = node['parent_id']
+        if parent_id is None:
+            tree.append(node)
+        else:
+            parent_node = node_dict.get(parent_id)
+            if parent_node is not None:
+                if 'children' not in parent_node or parent_node['children'] is None:
+                    parent_node['children'] = []
+                if node not in parent_node['children']:
+                    parent_node['children'].append(node)
+            else:
+                if node not in tree:
+                    tree.append(node)
+    
+    # 确保所有节点都有children字段
+    for node in tree:
+        if 'children' not in node:
+            node['children'] = None
+
+    return tree
+
+
+def recursive_to_tree(nodes: list[dict[str, Any]], *, parent_id: int | None = None) -> list[dict[str, Any]]:
+    """
+    通过递归算法构造树形结构（性能影响较大）
+
+    :param nodes: 树节点列表
+    :param parent_id: 父节点 ID，默认为 None 表示根节点
+    :return:
+    """
+    tree: list[dict[str, Any]] = []
+    for node in nodes:
+        if node['parent_id'] == parent_id:
+            child_nodes = recursive_to_tree(nodes, parent_id=node['id'])
+            if child_nodes:
+                node['children'] = child_nodes
+            tree.append(node)
+    return tree
+
+
 def bytes2human(n: int, format_str: str = '%(value).1f%(symbol)s') -> str:
     """
     字节数转人类可读格式