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/15_term.lua

@@ -0,0 +1,388 @@
+-- some term things
+-- e.g. redirects, read()
+
+local rc = ...
+
+-- we need a couple of these
+local colors = require("colors")
+local native = require("term")
+local strings = require("cc.strings")
+local expect = require("cc.expect").expect
+
+local term = {}
+package.loaded.term = term
+local thread = require("rc.thread")
+
+local valid = {
+  write = true,
+  scroll = true,
+  getCursorPos = true,
+  setCursorPos = true,
+  getCursorBlink = true,
+  setCursorBlink = true,
+  getSize = true,
+  clear = true,
+  clearLine = true,
+  getTextColor = true,
+  getTextColour = true,
+  setTextColor = true,
+  setTextColour = true,
+  getBackgroundColor = true,
+  getBackgroundColour = true,
+  setBackgroundColor = true,
+  setBackgroundColour = true,
+  isColor = true,
+  isColour = true,
+  blit = true,
+  setPaletteColor = true,
+  setPaletteColour = true,
+  getPaletteColor = true,
+  getPaletteColour = true,
+
+  -- LeonOS-PC graphics mode settings
+  setGraphicsMode = not not native.setGraphicsMode,
+  getGraphicsMode = not not native.getGraphicsMode,
+  drawPixels = not not native.drawPixels,
+  getPixels = not not native.getPixels,
+  setPixel = not not native.setPixel,
+  getPixel = not not native.getPixel
+}
+
+for k in pairs(valid) do
+  term[k] = function(...)
+    local redirect = thread.getTerm()
+    if not redirect[k] then
+      error("redirect object does not implement term."..k, 2)
+    end
+
+    return redirect[k](...)
+  end
+end
+
+function term.current()
+  return thread.getTerm()
+end
+
+function term.native()
+  return native
+end
+
+function term.redirect(obj)
+  expect(1, obj, "table")
+  return thread.setTerm(obj)
+end
+
+function term.at(x, y)
+  term.setCursorPos(x, y)
+  return term
+end
+
+local keys = require("keys")
+
+-- rc.write
+-- [[
+function rc.write(text)
+  expect(1, text, "string")
+
+  local lines = 0
+  local w, h = term.getSize()
+  local x, y = term.getCursorPos()
+
+  local elements = strings.splitElements(text, w)
+
+  strings.wrappedWriteElements(elements, w, false, {
+    newline = function()
+      lines = lines + 1
+
+      x = 1
+      if y >= h then
+        term.scroll(1)
+      else
+        y = y + 1
+      end
+
+      term.at(x, y)
+    end,
+
+    append = function(newText)
+      term.at(x, y).write(newText)
+      x = x + #newText
+    end,
+
+    getX = function()
+      return x
+    end
+  })
+
+  return lines
+end
+
+--]]
+
+-- old write() used for redrawing in read()
+local function write(text)
+  expect(1, text, "string")
+
+  local lines = 0
+  local w, h = term.getSize()
+
+  local function inc_cy(cy)
+    lines = lines + 1
+
+    if cy > h - 1 then
+      term.scroll(1)
+      return cy
+    else
+      return cy + 1
+    end
+  end
+
+  while #text > 0 do
+    local nl = text:find("\n") or #text
+    local chunk = text:sub(1, nl)
+    text = text:sub(#chunk + 1)
+
+    local has_nl = chunk:sub(-1) == "\n"
+    if has_nl then chunk = chunk:sub(1, -2) end
+
+    local cx, cy = term.getCursorPos()
+    while #chunk > 0 do
+      if cx > w then
+        term.setCursorPos(1, inc_cy(cy))
+        cx, cy = term.getCursorPos()
+      end
+
+      local to_write = chunk:sub(1, w - cx + 1)
+      term.write(to_write)
+
+      chunk = chunk:sub(#to_write + 1)
+      cx, cy = term.getCursorPos()
+    end
+
+    if has_nl then
+      term.setCursorPos(1, inc_cy(cy))
+    end
+  end
+
+  return lines
+end--]]
+
+rc.write = write
+
+-- read
+local empty = {}
+function term.read(replace, history, complete, default)
+  expect(1, replace, "string", "nil")
+  expect(2, history, "table", "nil")
+  expect(3, complete, "function", "nil")
+  expect(4, default, "string", "nil")
+
+  if replace then replace = replace:sub(1, 1) end
+  local hist = history or {}
+  history = {}
+  for i=1, #hist, 1 do
+    history[i] = hist[i]
+  end
+
+  local buffer = default or ""
+  local prev_buf = buffer
+  history[#history+1] = buffer
+
+  local hist_pos = #history
+  local cursor_pos = 0
+
+  local stx, sty = term.getCursorPos()
+  local w, h = term.getSize()
+
+  local dirty = false
+  local completions = {}
+  local comp_id = 0
+
+  local function clearCompletion()
+    if completions[comp_id] then
+      write((" "):rep(#completions[comp_id]))
+    end
+  end
+
+  local function full_redraw(force)
+    if force or dirty then
+      if complete and buffer ~= prev_buf then
+        completions = complete(buffer) or empty
+        comp_id = math.min(1, #completions)
+      end
+      prev_buf = buffer
+
+      term.setCursorPos(stx, sty)
+      local text = buffer
+      if replace then text = replace:rep(#text) end
+      local ln = write(text)
+
+      if completions[comp_id] then
+        local oldfg = term.getTextColor()
+        local oldbg = term.getBackgroundColor()
+        term.setTextColor(colors.white)
+        term.setBackgroundColor(colors.gray)
+        ln = ln + write(completions[comp_id])
+        term.setTextColor(oldfg)
+        term.setBackgroundColor(oldbg)
+      else
+        ln = ln + write(" ")
+      end
+
+      if sty + ln > h then
+        sty = sty - (sty + ln - h)
+      end
+    end
+
+    -- set cursor to the appropriate spot
+    local cx, cy = stx, sty
+    cx = cx + #buffer - cursor_pos-- + #(completions[comp_id] or "")
+    while cx > w do
+      cx = cx - w
+      cy = cy + 1
+    end
+    term.setCursorPos(cx, cy)
+  end
+
+  term.setCursorBlink(true)
+
+  while true do
+    full_redraw()
+    -- get input
+    local evt, id = rc.pullEvent()
+
+    if evt == "char" then
+      dirty = true
+      clearCompletion()
+      if cursor_pos == 0 then
+        buffer = buffer .. id
+      elseif cursor_pos == #buffer then
+        buffer = id .. buffer
+      else
+        buffer = buffer:sub(0, -cursor_pos - 1)..id..buffer:sub(-cursor_pos)
+      end
+
+    elseif evt == "paste" then
+      dirty = true
+      clearCompletion()
+      if cursor_pos == 0 then
+        buffer = buffer .. id
+      elseif cursor_pos == #buffer then
+        buffer = id .. buffer
+      else
+        buffer = buffer:sub(0, -cursor_pos - 1)..id..
+          buffer:sub(-cursor_pos+(#id-1))
+      end
+
+    elseif evt == "key" then
+      id = keys.getName(id)
+
+      if id == "backspace" and #buffer > 0 then
+        dirty = true
+        if cursor_pos == 0 then
+          buffer = buffer:sub(1, -2)
+          clearCompletion()
+        elseif cursor_pos < #buffer then
+          buffer = buffer:sub(0, -cursor_pos - 2)..buffer:sub(-cursor_pos)
+        end
+
+      elseif id == "delete" and cursor_pos > 0 then
+        dirty = true
+
+        if cursor_pos == #buffer then
+          buffer = buffer:sub(2)
+        elseif cursor_pos == 1 then
+          buffer = buffer:sub(1, -2)
+        else
+          buffer = buffer:sub(0, -cursor_pos - 1) .. buffer:sub(-cursor_pos + 1)
+        end
+        cursor_pos = cursor_pos - 1
+
+      elseif id == "up" then
+        if #completions > 1 then
+          dirty = true
+          clearCompletion()
+          if comp_id > 1 then
+            comp_id = comp_id - 1
+          else
+            comp_id = #completions
+          end
+
+        elseif hist_pos > 1 then
+          cursor_pos = 0
+
+          history[hist_pos] = buffer
+          hist_pos = hist_pos - 1
+
+          buffer = (" "):rep(#buffer)
+          full_redraw(true)
+
+          buffer = history[hist_pos]
+          dirty = true
+        end
+
+      elseif id == "down" then
+        if #completions > 1 then
+          dirty = true
+          clearCompletion()
+          if comp_id < #completions then
+            comp_id = comp_id + 1
+          else
+            comp_id = 1
+          end
+
+        elseif hist_pos < #history then
+          cursor_pos = 0
+
+          history[hist_pos] = buffer
+          hist_pos = hist_pos + 1
+
+          buffer = (" "):rep(#buffer)
+          full_redraw(true)
+
+          buffer = history[hist_pos]
+          dirty = true
+        end
+
+      elseif id == "left" then
+        if cursor_pos < #buffer then
+          clearCompletion()
+          cursor_pos = cursor_pos + 1
+        end
+
+      elseif id == "right" then
+        if cursor_pos > 0 then
+          cursor_pos = cursor_pos - 1
+
+        elseif comp_id > 0 then
+          dirty = true
+          buffer = buffer .. completions[comp_id]
+        end
+
+      elseif id == "tab" then
+        if comp_id > 0 then
+          dirty = true
+          buffer = buffer .. completions[comp_id]
+        end
+
+      elseif id == "home" then
+        cursor_pos = #buffer
+
+      elseif id == "end" then
+        cursor_pos = 0
+
+      elseif id == "enter" then
+        clearCompletion()
+        write("\n")
+        break
+      end
+    end
+  end
+
+  term.setCursorBlink(false)
+
+  return buffer
+end
+
+rc.read = term.read
+setmetatable(term, {__index = native})