feat: 初始提交 LeonOS 实现

添加 LeonOS 的基本实现，包括：
- 核心 API 模块（colors, disk, gps, keys, multishell, parallel, rednet, redstone, settings, vector）
- 命令行程序（about, alias, bg, clear, copy, delete, edit, fg, help, list, lua, mkdir, move, paint, peripherals, programs, reboot, set, shutdown, threads）
- 系统启动脚本和包管理
- 文档（README.md, LICENSE）
- 开发工具（devbin）和更新程序

实现功能：
- 完整的线程管理系统
- 兼容 ComputerCraft 的 API 设计
- 改进的 shell 和命令补全系统
- 多标签终端支持
- 设置管理系统

data/computercraft/lua/rom/startup/10_package.lua

@@ -0,0 +1,131 @@
+-- package library --
+
+local rc = ...
+
+_G.package = {}
+
+package.config = "/\n;\n?\n!\n-"
+package.cpath = ""
+package.path = "/rc/apis/?.lua;/rc/modules/main/?.lua;./lib/?.lua;./lib/?/init.lua;./?.lua;./?/init.lua"
+
+local function rm(api)
+  local tab = _G[api]
+  _G[api] = nil
+  return tab
+end
+
+package.loaded = {
+  _G = _G,
+  os = os,
+  rc = rc,
+  math = math,
+  utf8 = utf8,
+  table = table,
+  debug = debug,
+  bit32 = rawget(_G, "bit32"),
+  string = string,
+  package = package,
+  coroutine = coroutine,
+
+  -- CC-specific ones
+  peripheral = rm("peripheral"),
+  redstone = rm("redstone"),
+  commands = rm("commands"),
+  pocket = rm("pocket"),
+  turtle = rm("turtle"),
+  http = rm("http"),
+  term = rm("term"),
+  fs = rm("fs"),
+  rs = rm("rs"),
+
+  -- LeonOS-PC APIs
+  periphemu = rm("periphemu"),
+  mounter = rm("mounter"),
+  config = rm("config"),
+
+  -- CCEmuX API
+  ccemux = rm("ccemux")
+}
+
+package.preload = {}
+
+package.searchers = {
+  -- check package.preload
+  function(mod)
+    if package.preload[mod] then
+      return package.preload[mod]
+    else
+      return nil, "no field package.preload['" .. mod .. "']"
+    end
+  end,
+
+  -- check for lua library
+  function(mod)
+    local ok, err = package.searchpath(mod, package.path, ".", "/")
+    if not ok then
+      return nil, err
+    end
+
+    local func, loaderr = loadfile(ok)
+    if not func then
+      return nil, loaderr
+    end
+    return func()
+  end,
+}
+
+local fs = package.loaded.fs
+-- require isn't here yet
+local expect = loadfile("/rc/modules/main/cc/expect.lua")()
+package.loaded["cc.expect"] = expect
+
+function package.searchpath(name, path, sep, rep)
+  expect(1, name, "string")
+  expect(2, path, "string")
+  expect(3, sep, "string", "nil")
+  expect(4, rep, "string", "nil")
+
+  sep = "%" .. (sep or ".")
+  rep = rep or "/"
+
+  name = name:gsub(sep, rep)
+  local serr = ""
+
+  for search in path:gmatch("[^;]+") do
+    search = search:gsub("%?", name)
+
+    if fs.exists(search) then
+      return search
+
+    else
+      if #serr > 0 then
+        serr = serr .. "\n  "
+      end
+
+      serr = serr .. "no file '" .. search .. "'"
+    end
+  end
+
+  return nil, serr
+end
+
+function _G.require(mod)
+  expect(1, mod, "string")
+
+  if package.loaded[mod] then
+    return package.loaded[mod]
+  end
+
+  local serr = "module '" .. mod .. "' not found:"
+  for _, searcher in ipairs(package.searchers) do
+    local result, err = searcher(mod)
+    if result then
+      package.loaded[mod] = result
+      return result
+    else
+      serr = serr .. "\n  " .. err
+    end
+  end
+
+  error(serr, 2)
+end