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/modules/main/cc/strings.lua

@@ -0,0 +1,133 @@
+-- cc.strings
+
+local term = require("term")
+local expectlib = require("cc.expect")
+local expect = expectlib.expect
+local field = expectlib.field
+local strings = {}
+
+local function count(...)
+  local tab = table.pack(...)
+  local n = 0
+
+  for i=1, tab.n, 1 do
+    if tab[i] then n = n + 1 end
+  end
+
+  return n
+end
+
+function strings.splitElements(text, limit)
+  expect(1, text, "string")
+  expect(2, limit, "number", "nil")
+
+  local tokens = {}
+
+  while #text > 0 do
+    local ws = text:match("^[ \t]+")
+    local nl = text:match("^\n+")
+    local sep = text:match("^[%-%+%*]")
+    local word = text:match("^[^ \t\n%-%+%*]+")
+
+    if count(ws, nl, sep, word) > 1 then
+      error(("Edge case: %q, %q, %q, %q"):format(ws, nl, sep, word), 0)
+    end
+
+    local token = ws or nl or sep or word
+    text = text:sub(#token + 1)
+
+    while #token > 0 do
+      local ttext = token:sub(1, limit or 65535)
+      token = token:sub(#ttext + 1)
+
+      tokens[#tokens+1] = { text = ttext, type = ws and "ws" or nl and "nl"
+        or sep and "word" or word and "word" }
+    end
+  end
+
+  return tokens
+end
+
+function strings.wrappedWriteElements(elements, width, doHalves, handler)
+  expect(1, elements, "table")
+  expect(2, width, "number")
+  expect(3, doHalves, "boolean", "nil")
+  expect(4, handler, "table")
+
+  field(handler, "newline", "function")
+  field(handler, "append", "function")
+  field(handler, "getX", "function")
+
+  for i=1, #elements, 1 do
+    local e = elements[i]
+
+    if e.type == "nl" then
+      for _=1, #e.text do handler.newline() end
+
+    elseif e.type == "ws" then
+      local x = handler.getX()
+
+      if x + #e.text > width + 1 then
+        handler.newline()
+
+      else
+        handler.append(e.text)
+      end
+
+    elseif e.type == "word" then
+      local x = handler.getX()
+      local half = math.ceil(#e.text / 2)
+
+      if x + #e.text > width + 1 then
+        if doHalves and x + half < width and #e.text > width/2 then
+          local halfText = e.text:sub(1, math.floor(#e.text / 2)) .. "-"
+          e.text = e.text:sub(#halfText)
+          handler.append(halfText)
+          handler.newline()
+
+        elseif x > 1 then
+          handler.newline()
+        end
+      end
+
+      handler.append(e.text)
+    end
+  end
+end
+
+function strings.wrap(text, width, doHalves)
+  expect(1, text, "string")
+  expect(2, width, "number", "nil")
+  expect(3, doHalves, "boolean", "nil")
+
+  width = width or term.getSize()
+
+  local lines = { "" }
+  local elements = strings.splitElements(text, width)
+
+  strings.wrappedWriteElements(elements, width, doHalves, {
+    newline = function()
+      lines[#lines+1] = ""
+    end,
+
+    append = function(newText)
+      lines[#lines] = lines[#lines] .. newText
+    end,
+
+    getX = function()
+      return #lines[#lines]
+    end
+  })
+
+  return lines
+end
+
+function strings.ensure_width(line, width)
+  expect(1, line, "string")
+  expect(2, width, "number", "nil")
+  width = width or term.getSize()
+
+  return (line .. (" "):rep(width - #line)):sub(1, width)
+end
+
+return strings