feat: 添加时间显示和图片查看程序并更新安装器版本

- 添加 time.lua 程序用于显示和格式化当前时间
- 添加 imageview.lua 程序用于从URL加载和显示图片
- 添加 pkg_download_en.hlp 帮助文档说明包管理功能
- 更新安装器版本号至 0.3.7 Beta 7

data/computercraft/lua/rom/help/pkg_download_en.hlp

@@ -0,0 +1,91 @@
+=== How to Download Packages ===
+
+In LeonOS, you can use the `pkg` command to download and install software packages. This help document will detailed explain how to use this command.
+
+== Basic Usage ==
+
+Download and install a package:
+```
+pkg install <package_name>
+```
+
+== Command Options ==
+
+The `pkg install` command supports the following options:
+
+- `-f`, `--force`: Force installation, overwrite existing files
+- `-v`, `--verbose`: Show detailed installation process
+- `-h`, `--help`: Show help information
+
+== Usage Examples ==
+
+1. Install a package:
+```
+pkg install example-package
+```
+
+2. Force install a package:
+```
+pkg install --force example-package
+```
+
+3. Install a package with detailed information:
+```
+pkg install -v example-package
+```
+
+4. View help for `pkg install` command:
+```
+pkg install --help
+```
+
+== Search for Packages ==
+
+Before installing a package, you can search for available packages:
+```
+pkg search <search_keyword>
+```
+
+Example:
+```
+pkg search editor
+```
+
+== View Package Information ==
+
+Before installing a package, you can view detailed information about it:
+```
+pkg info <package_name>
+```
+
+Example:
+```
+pkg info example-package
+```
+
+== Update Packages ==
+
+You can update installed packages using the following command:
+```
+pkg update <package_name>
+```
+
+If you don't specify a package name, all installed packages will be updated:
+```
+pkg update
+```
+
+== Frequently Asked Questions ==
+
+Q: What should I do if I encounter a network error when downloading a package?
+A: Please check your network connection to ensure you can access the Internet. If the problem persists, please try again later.
+
+Q: How can I view installed packages?
+A: You can use the `pkg list` command to view all installed packages.
+
+Q: Where can I get package names?
+A: You can search for packages using the `pkg search` command or check the official package repository list.
+
+== Exit Help ==
+
+Press the ESC key to exit the help document.

data/computercraft/lua/rom/programs/imageview.lua

@@ -0,0 +1,92 @@
+-- imageview.lua: Image viewer that loads from URL
+local http = require("http")
+local paintutils = require("paintutils")
+local term = require("term")
+local event = require("event")
+local shell = require("shell")
+
+-- 帮助信息函数
+local function printHelp()
+  print("Usage: imageview <image_url>")
+  print("Options:")
+  print("  --help, -h    Show this help message")
+  print("
+Displays an image from the specified URL.
+Press ESC to exit back to shell.")
+end
+
+-- 下载图片函数
+local function downloadImage(url)
+  print("Downloading image from: " .. url)
+  local response, err = http.get(url, nil, true)
+  if not response then
+    print("Error downloading image: " .. err)
+    return nil
+  end
+
+  local data = response.readAll()
+  response.close()
+  return data
+end
+
+-- 主函数
+local function main(args)
+  -- 处理命令行参数
+  if #args == 0 or args[1] == "--help" or args[1] == "-h" then
+    printHelp()
+    return
+  end
+
+  local imageUrl = args[1]
+
+  -- 检查是否是有效的URL
+  if not imageUrl:match("^https?://") then
+    print("Error: Invalid URL format. Must start with http:// or https://")
+    return
+  end
+
+  -- 下载图片
+  local imageData = downloadImage(imageUrl)
+  if not imageData then
+    return
+  end
+
+  -- 尝试加载图片
+  local success, image = pcall(function()
+    return paintutils.loadImage(imageData)
+  end)
+
+  if not success then
+    print("Error loading image: " .. image)
+    return
+  end
+
+  -- 清除屏幕并显示图片
+  term.clear()
+  local w, h = term.getSize()
+
+  -- 计算图片居中位置
+  local imgW, imgH = #image[1], #image
+  local x = math.floor((w - imgW) / 2)
+  local y = math.floor((h - imgH) / 2)
+
+  -- 绘制图片
+  paintutils.drawImage(image, x, y)
+
+  print("\nImage displayed. Press ESC to exit.")
+
+  -- 监听ESC键
+  while true do
+    local _, key = event.pull("key")
+    if key == 27 then -- ESC键
+      term.clear()
+      term.setCursorPos(1, 1)
+      print("Image viewer closed.")
+      return
+    end
+  end
+end
+
+-- 运行主函数
+local args = {...}
+main(args)

data/computercraft/lua/rom/programs/time.lua

@@ -0,0 +1,66 @@
+-- time.lua: Display current time
+local shell = require("shell")
+
+-- 帮助信息函数
+local function printHelp()
+  print("Usage: time [options]")
+  print("Options:")
+  print("  --help, -h       Show this help message")
+  print("  --format, -f <fmt>  Specify time format string (see below for details)")
+  print("
+Formats for --format option:")
+  print("  %Y: Year (4 digits)")
+  print("  %m: Month (01-12)")
+  print("  %d: Day (01-31)")
+  print("  %H: Hour (00-23)")
+  print("  %M: Minute (00-59)")
+  print("  %S: Second (00-59)")
+  print("  %A: Full weekday name")
+  print("  %B: Full month name")
+  print("
+Examples:")
+  print("  time                     # Show current time in default format")
+  print("  time --format '%Y-%m-%d %H:%M:%S'  # Show time as YYYY-MM-DD HH:MM:SS")
+  print("  time -f '%A, %B %d, %Y'  # Show time as 'Monday, January 01, 2023'")
+end
+
+-- 主函数
+local function main(args)
+  -- 处理命令行参数
+  local showHelp = false
+  local formatStr = "%Y-%m-%d %H:%M:%S"
+  local i = 1
+
+  while i <= #args do
+    if args[i] == "--help" or args[i] == "-h" then
+      showHelp = true
+    elseif args[i] == "--format" or args[i] == "-f" then
+      i = i + 1
+      if i <= #args then
+        formatStr = args[i]
+      else
+        print("Error: Missing format string for --format option")
+        return
+      end
+    else
+      print("Error: Unknown option '" .. args[i] .. "'\n")
+      printHelp()
+      return
+    end
+    i = i + 1
+  end
+
+  if showHelp then
+    printHelp()
+    return
+  end
+
+  -- 获取并显示当前时间
+  local currentTime = os.time()
+  local formattedTime = os.date(formatStr, currentTime)
+  print(formattedTime)
+end
+
+-- 运行主函数
+local args = {...}
+main(args)