feat(settings): add preferred terminal selection

Allow users to choose their preferred terminal app for opening
provider terminals. Supports platform-specific options:
- macOS: Terminal.app, iTerm2, Alacritty, Kitty, Ghostty
- Windows: cmd, PowerShell, Windows Terminal
- Linux: GNOME Terminal, Konsole, Xfce4, Alacritty, Kitty, Ghostty

Falls back to system default if selected terminal is unavailable.

src/components/settings/SettingsPage.tsx

@@ -36,6 +36,7 @@ import { ThemeSettings } from "@/components/settings/ThemeSettings";
 import { WindowSettings } from "@/components/settings/WindowSettings";
 import { AppVisibilitySettings } from "@/components/settings/AppVisibilitySettings";
 import { SkillSyncMethodSettings } from "@/components/settings/SkillSyncMethodSettings";
+import { TerminalSettings } from "@/components/settings/TerminalSettings";
 import { DirectorySettings } from "@/components/settings/DirectorySettings";
 import { ImportExportSection } from "@/components/settings/ImportExportSection";
 import { AboutSection } from "@/components/settings/AboutSection";
@@ -256,6 +257,12 @@ export function SettingsPage({
                       handleAutoSave({ skillSyncMethod: method })
                     }
                   />
+                  <TerminalSettings
+                    value={settings.preferredTerminal}
+                    onChange={(terminal) =>
+                      handleAutoSave({ preferredTerminal: terminal })
+                    }
+                  />
                 </motion.div>
               ) : null}
             </TabsContent>

src/components/settings/TerminalSettings.tsx

@@ -0,0 +1,111 @@
+import { useTranslation } from "react-i18next";
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from "@/components/ui/select";
+import { isMac, isWindows, isLinux } from "@/lib/platform";
+
+// Terminal options per platform
+const MACOS_TERMINALS = [
+  { value: "terminal", labelKey: "settings.terminal.options.macos.terminal" },
+  { value: "iterm2", labelKey: "settings.terminal.options.macos.iterm2" },
+  { value: "alacritty", labelKey: "settings.terminal.options.macos.alacritty" },
+  { value: "kitty", labelKey: "settings.terminal.options.macos.kitty" },
+  { value: "ghostty", labelKey: "settings.terminal.options.macos.ghostty" },
+] as const;
+
+const WINDOWS_TERMINALS = [
+  { value: "cmd", labelKey: "settings.terminal.options.windows.cmd" },
+  {
+    value: "powershell",
+    labelKey: "settings.terminal.options.windows.powershell",
+  },
+  { value: "wt", labelKey: "settings.terminal.options.windows.wt" },
+] as const;
+
+const LINUX_TERMINALS = [
+  {
+    value: "gnome-terminal",
+    labelKey: "settings.terminal.options.linux.gnomeTerminal",
+  },
+  { value: "konsole", labelKey: "settings.terminal.options.linux.konsole" },
+  {
+    value: "xfce4-terminal",
+    labelKey: "settings.terminal.options.linux.xfce4Terminal",
+  },
+  { value: "alacritty", labelKey: "settings.terminal.options.linux.alacritty" },
+  { value: "kitty", labelKey: "settings.terminal.options.linux.kitty" },
+  { value: "ghostty", labelKey: "settings.terminal.options.linux.ghostty" },
+] as const;
+
+// Get terminals for the current platform
+function getTerminalOptions() {
+  if (isMac()) {
+    return MACOS_TERMINALS;
+  }
+  if (isWindows()) {
+    return WINDOWS_TERMINALS;
+  }
+  if (isLinux()) {
+    return LINUX_TERMINALS;
+  }
+  // Fallback to macOS options
+  return MACOS_TERMINALS;
+}
+
+// Get default terminal for the current platform
+function getDefaultTerminal(): string {
+  if (isMac()) {
+    return "terminal";
+  }
+  if (isWindows()) {
+    return "cmd";
+  }
+  if (isLinux()) {
+    return "gnome-terminal";
+  }
+  return "terminal";
+}
+
+export interface TerminalSettingsProps {
+  value?: string;
+  onChange: (value: string) => void;
+}
+
+export function TerminalSettings({ value, onChange }: TerminalSettingsProps) {
+  const { t } = useTranslation();
+  const terminals = getTerminalOptions();
+  const defaultTerminal = getDefaultTerminal();
+
+  // Use value or default
+  const currentValue = value || defaultTerminal;
+
+  return (
+    <section className="space-y-2">
+      <header className="space-y-1">
+        <h3 className="text-sm font-medium">{t("settings.terminal.title")}</h3>
+        <p className="text-xs text-muted-foreground">
+          {t("settings.terminal.description")}
+        </p>
+      </header>
+      <Select value={currentValue} onValueChange={onChange}>
+        <SelectTrigger className="w-[200px]">
+          <SelectValue />
+        </SelectTrigger>
+        <SelectContent>
+          {terminals.map((terminal) => (
+            <SelectItem key={terminal.value} value={terminal.value}>
+              {t(terminal.labelKey)}
+            </SelectItem>
+          ))}
+        </SelectContent>
+      </Select>
+      <p className="text-xs text-muted-foreground">
+        {t("settings.terminal.fallbackHint")}
+      </p>
+    </section>
+  );
+}