Revert "feat(settings): add auto-launch on system startup feature"

This reverts commit ba336fc416.

Reason: Found issues that need to be addressed before reintroducing
the auto-launch feature. Will reimplement with fixes.

src/i18n/locales/en.json

@@ -166,9 +166,6 @@
     "languageOptionEnglish": "English",
     "windowBehavior": "Window Behavior",
     "windowBehaviorHint": "Configure window minimize and Claude plugin integration policies.",
-    "launchOnStartup": "Launch on Startup",
-    "launchOnStartupDescription": "Automatically run CC Switch when system starts",
-    "autoLaunchFailed": "Failed to set auto-launch",
     "minimizeToTray": "Minimize to tray on close",
     "minimizeToTrayDescription": "When checked, clicking the close button will hide to system tray, otherwise the app will exit directly.",
     "enableClaudePluginIntegration": "Apply to Claude Code extension",

src/i18n/locales/zh.json

@@ -166,9 +166,6 @@
     "languageOptionEnglish": "English",
     "windowBehavior": "窗口行为",
     "windowBehaviorHint": "配置窗口最小化与 Claude 插件联动策略。",
-    "launchOnStartup": "开机自启",
-    "launchOnStartupDescription": "随系统启动自动运行 CC Switch",
-    "autoLaunchFailed": "设置开机自启失败",
     "minimizeToTray": "关闭时最小化到托盘",
     "minimizeToTrayDescription": "勾选后点击关闭按钮会隐藏到系统托盘，取消则直接退出应用。",
     "enableClaudePluginIntegration": "应用到 Claude Code 插件",