feat: 国际化支持，英文源串+中文翻译

全部44处qsTr源串改为英文，新建translations/jnetapplet_zh_CN.ts
中文翻译文件。CMake增加LinguistTools+qt_add_translation编译
.ts->.qm，init()按系统语言加载.qm并安装到qApp。

中文系统显示中文翻译，英文系统显示英文源串。

translations/jnetapplet_zh_CN.ts

@@ -0,0 +1,241 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!DOCTYPE TS>
+<TS version="2.1" language="zh_CN">
+<context>
+    <name>AboutWindow</name>
+    <message>
+        <location filename="../package/components/AboutWindow.qml" line="86"/>
+        <source>About</source>
+        <translation>关于</translation>
+    </message>
+    <message>
+        <location filename="../package/components/AboutWindow.qml" line="133"/>
+        <source>Network Speed Monitor</source>
+        <translation>网络速度监控</translation>
+    </message>
+    <message>
+        <location filename="../package/components/AboutWindow.qml" line="182"/>
+        <source>Version</source>
+        <translation>版本</translation>
+    </message>
+    <message>
+        <location filename="../package/components/AboutWindow.qml" line="203"/>
+        <source>Author</source>
+        <translation>作者</translation>
+    </message>
+    <message>
+        <location filename="../package/components/AboutWindow.qml" line="224"/>
+        <source>Description</source>
+        <translation>描述</translation>
+    </message>
+    <message>
+        <location filename="../package/components/AboutWindow.qml" line="232"/>
+        <source>Monitor network speed and traffic</source>
+        <translation>监控网络速度和流量</translation>
+    </message>
+    <message>
+        <location filename="../package/components/AboutWindow.qml" line="246"/>
+        <source>Repository</source>
+        <translation>仓库</translation>
+    </message>
+    <message>
+        <location filename="../package/components/AboutWindow.qml" line="284"/>
+        <source>Copied</source>
+        <translation>已复制</translation>
+    </message>
+</context>
+<context>
+    <name>NetworkPopup</name>
+    <message>
+        <location filename="../package/components/NetworkPopup.qml" line="98"/>
+        <source>Network Speed Monitor</source>
+        <translation>网络速度监控</translation>
+    </message>
+    <message>
+        <location filename="../package/components/NetworkPopup.qml" line="129"/>
+        <source>IPv4: </source>
+        <translation>IPv4：</translation>
+    </message>
+    <message>
+        <location filename="../package/components/NetworkPopup.qml" line="138"/>
+        <source>IPv6: </source>
+        <translation>IPv6：</translation>
+    </message>
+    <message>
+        <location filename="../package/components/NetworkPopup.qml" line="190"/>
+        <source>Download</source>
+        <translation>下载</translation>
+    </message>
+    <message>
+        <location filename="../package/components/NetworkPopup.qml" line="247"/>
+        <source>Upload</source>
+        <translation>上传</translation>
+    </message>
+    <message>
+        <location filename="../package/components/NetworkPopup.qml" line="282"/>
+        <source>Total</source>
+        <translation>总计</translation>
+    </message>
+    <message>
+        <location filename="../package/components/NetworkPopup.qml" line="459"/>
+        <source>No network interface detected</source>
+        <translation>未检测到网络接口</translation>
+    </message>
+</context>
+<context>
+    <name>SettingsWindow</name>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="54"/>
+        <location filename="../package/components/SettingsWindow.qml" line="383"/>
+        <location filename="../package/components/SettingsWindow.qml" line="560"/>
+        <source>Uninstall Plugin</source>
+        <translation>卸载插件</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="73"/>
+        <source>Loopback</source>
+        <translation>本地回环</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="74"/>
+        <source>Virtual Interface</source>
+        <translation>虚拟接口</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="75"/>
+        <source>Wired Network</source>
+        <translation>有线网络</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="76"/>
+        <source>Wireless Network</source>
+        <translation>无线网络</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="77"/>
+        <source>Container Network</source>
+        <translation>容器网络</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="78"/>
+        <source>Bridge</source>
+        <translation>桥接</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="79"/>
+        <source>VPN</source>
+        <translation>VPN</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="80"/>
+        <source>Virtual Bridge</source>
+        <translation>虚拟桥接</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="81"/>
+        <source>Other</source>
+        <translation>其他</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="142"/>
+        <source>Settings</source>
+        <translation>设置</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="196"/>
+        <source>Network Interface</source>
+        <translation>网络接口</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="349"/>
+        <source>No network interface detected</source>
+        <translation>未检测到网络接口</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="360"/>
+        <source>Font Color</source>
+        <translation>字体颜色</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="446"/>
+        <source>Warning</source>
+        <translation>警告</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="454"/>
+        <source>The following command uninstalls the plugin and restarts dde-shell. Please copy and run it in terminal:</source>
+        <translation>以下命令用于卸载插件并重启 dde-shell，请复制到终端中执行：</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="499"/>
+        <source>Cancel</source>
+        <translation>取消</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="522"/>
+        <source>Copy Command</source>
+        <translation>复制命令</translation>
+    </message>
+    <message>
+        <location filename="../package/components/SettingsWindow.qml" line="539"/>
+        <source>Uninstall command copied to clipboard. Please paste and run it in terminal.</source>
+        <translation>卸载命令已复制到剪贴板，请在终端中粘贴执行</translation>
+    </message>
+</context>
+<context>
+    <name>TrafficChartWindow</name>
+    <message>
+        <location filename="../package/components/TrafficChartWindow.qml" line="180"/>
+        <source>Traffic Chart</source>
+        <translation>流量波动图</translation>
+    </message>
+    <message>
+        <location filename="../package/components/TrafficChartWindow.qml" line="424"/>
+        <source>No history data</source>
+        <translation>暂无历史数据</translation>
+    </message>
+    <message>
+        <location filename="../package/components/TrafficChartWindow.qml" line="581"/>
+        <source>Hover over the curve for details</source>
+        <translation>鼠标移到曲线上查看详情</translation>
+    </message>
+</context>
+<context>
+    <name>networkview</name>
+    <message>
+        <location filename="../package/networkview.qml" line="225"/>
+        <source>IPv4: </source>
+        <translation>IPv4：</translation>
+    </message>
+    <message>
+        <location filename="../package/networkview.qml" line="225"/>
+        <source>None</source>
+        <translation>无</translation>
+    </message>
+    <message>
+        <location filename="../package/networkview.qml" line="226"/>
+        <source>IPv6: </source>
+        <translation>IPv6：</translation>
+    </message>
+    <message>
+        <location filename="../package/networkview.qml" line="227"/>
+        <source>No network interface detected</source>
+        <translation>未检测到网络接口</translation>
+    </message>
+    <message>
+        <location filename="../package/networkview.qml" line="303"/>
+        <source>Settings</source>
+        <translation>设置</translation>
+    </message>
+    <message>
+        <location filename="../package/networkview.qml" line="313"/>
+        <source>Traffic Chart</source>
+        <translation>流量波动图</translation>
+    </message>
+    <message>
+        <location filename="../package/networkview.qml" line="324"/>
+        <source>About</source>
+        <translation>关于</translation>
+    </message>
+</context>
+</TS>