feat: add async demo support and enhance template resolution

- Introduced async demo functionality in the README, allowing for asynchronous data preparation before rendering components.
- Updated WccDashboard, WccProperties, and WccSidebar to support Promise-based template factories.
- Implemented resolveTemplateFactory to handle both synchronous and asynchronous template results.
- Added tests for resolveTemplateFactory to ensure correct behavior for both sync and async templates.
- Updated pnpm workspace configuration.

ts_web/elements/wcctools.helpers.ts

@@ -0,0 +1,9 @@
+import type { TemplateResult } from 'lit';
+
+export type TTemplateFactory = () => TemplateResult | Promise<TemplateResult>;
+
+export const resolveTemplateFactory = async (
+  factoryArg: TTemplateFactory
+): Promise<TemplateResult> => {
+  return await Promise.resolve(factoryArg());
+};