feat(desktop): split daemon and release settings to main process

Move daemon management and release channel settings out of the renderer's
AsyncStorage and into a desktop-owned settings store persisted by the main
process. Adds a "Keep daemon running after quit" option, a daemon lifecycle
section in settings, and a one-time migration of legacy renderer-owned
desktop settings.

packages/desktop/src/settings/desktop-settings-commands.ts

@@ -0,0 +1,15 @@
+import type { DesktopSettingsStore } from "./desktop-settings.js";
+
+export type DesktopCommandHandler = (args?: Record<string, unknown>) => Promise<unknown> | unknown;
+
+export function createDesktopSettingsCommandHandlers({
+  settingsStore,
+}: {
+  settingsStore: DesktopSettingsStore;
+}): Record<string, DesktopCommandHandler> {
+  return {
+    get_desktop_settings: () => settingsStore.get(),
+    patch_desktop_settings: (args) => settingsStore.patch(args),
+    migrate_legacy_desktop_settings: (args) => settingsStore.migrateLegacyRendererSettings(args),
+  };
+}