Move settings into a standalone Settings window

The tab-bar popover had outgrown itself. Settings now open in their own
native window (a fourth window kind, built like the connection manager but
not modal): a sidebar with Appearance, Transfers, Editor, File list and
About, holding every popover row plus the visible-columns choice. Each
control is an ordinary settings save, so the other windows follow live
while it stays open.

The gear button in the tab bar, Ctrl+, and the macOS app menu's
"Settings..." (Cmd+,) open it. On macOS Cmd+W arrives as the main window's
close-tab menu action, so bun closes the focused Settings window first
instead of a main-window tab.

Co-Authored-By: Claude <noreply@anthropic.com>

src/shared/i18n/es.ts

@@ -23,14 +23,22 @@ export const es = {
 		manageConnections: "Gestionar conexiones",
 		newTab: "Nueva pestaña ({mod}T)",
 		closeTab: "Cerrar pestaña ({mod}W)",
-		options: "Opciones",
+		options: "Ajustes",
 		update: "Actualización disponible",
 		updating: "Actualizando",
 		restartToUpdate: "Reiniciar para aplicar",
 		updateTooltip: "Actualización disponible: miniSCP {version}",
 	},
 	options: {
-		title: "Opciones",
+		title: "Ajustes",
+		sections: {
+			appearance: "Apariencia",
+			transfers: "Transferencias",
+			editor: "Editor",
+			fileList: "Lista de archivos",
+			about: "Acerca de",
+		},
+		columns: "Columnas visibles",
 		language: "Idioma",
 		system: "Sistema",
 		theme: { label: "Tema", system: "Sistema", light: "Claro", dark: "Oscuro" },
@@ -248,6 +256,7 @@ export const es = {
 	},
 	menu: {
 		about: "Acerca de {app}",
+		settings: "Ajustes…",
 		checkForUpdates: "Buscar actualizaciones…",
 		quit: "Salir",
 		file: "Archivo",