feat(包管理器): 实现LeonOS包管理系统基础功能

添加包管理器核心程序(pkg.lua)及相关支持文件
- 实现包安装、更新、移除、列表、搜索等功能
- 添加包元数据结构和本地存储管理
- 包含示例包和命令补全支持
- 更新系统版本至0.3.0

data/computercraft/lua/rom/programs/tree.lua

@@ -0,0 +1,93 @@
+-- tree
+
+-- 程序顶部名称栏
+local term = require("term")
+local colors = require("colors")
+
+-- 保存当前颜色设置
+local old_fg = term.getTextColor()
+local old_bg = term.getBackgroundColor()
+
+-- 设置名称栏颜色并显示
+term.setTextColor(colors.white)
+term.setBackgroundColor(colors.cyan)
+term.at(1, 1).clearLine()
+term.at(1, 1).write("=== Directory Tree Utility ===")
+
+-- 恢复颜色设置
+term.setTextColor(old_fg)
+term.setBackgroundColor(old_bg)
+term.at(1, 2)
+
+local args = {...}
+local fs = require("fs")
+local shell = require("shell")
+local settings = require("settings")
+
+if #args == 0 then args[1] = shell.dir() end
+
+local show_hidden = settings.get("list.show_hidden")
+
+-- 递归打印目录树
+local function print_tree(dir, prefix, is_last)
+  if not fs.exists(dir) then
+    error(dir .. ": that directory does not exist", 0)
+  elseif not fs.isDir(dir) then
+    error(dir .. ": not a directory", 0)
+  end
+
+  local raw_files = fs.list(dir)
+  local files, dirs = {}, {}
+
+  -- 分离目录和文件
+  for i=1, #raw_files, 1 do
+    local full = fs.combine(dir, raw_files[i])
+
+    if raw_files[i]:sub(1,1) ~= "." or show_hidden then
+      if fs.isDir(full) then
+        dirs[#dirs+1] = raw_files[i]
+      else
+        files[#files+1] = raw_files[i]
+      end
+    end
+  end
+
+  -- 排序目录和文件
+  table.sort(dirs)
+  table.sort(files)
+
+  -- 打印当前目录
+  if prefix == "" then
+    term.setTextColor(colors.yellow)
+    print(dir)
+    term.setTextColor(old_fg)
+  end
+
+  -- 打印目录
+  for i=1, #dirs, 1 do
+    local is_last_dir = (i == #dirs and #files == 0)
+    local connector = is_last_dir and "└── " or "├── "
+    local new_prefix = prefix .. (is_last_dir and "    " or "│   ")
+
+    term.setTextColor(colors.green)
+    print(prefix .. connector .. dirs[i])
+    term.setTextColor(old_fg)
+
+    -- 递归打印子目录
+    print_tree(fs.combine(dir, dirs[i]), new_prefix, is_last_dir)
+  end
+
+  -- 打印文件
+  for i=1, #files, 1 do
+    local is_last_file = (i == #files)
+    local connector = is_last_file and "└── " or "├── "
+
+    term.setTextColor(colors.white)
+    print(prefix .. connector .. files[i])
+    term.setTextColor(old_fg)
+  end
+end
+
+for i=1, #args, 1 do
+  print_tree(args[i], "", true)
+end