Async Render Default

### Description
The current state of asynchronous rendering only applies to sections that depend on loaders or actions exceeding a specific time threshold. While this is beneficial, there are some drawbacks:

Sections that render larger HTML can increase render duration and Time to First Byte (TTFB).
Users lack the flexibility to choose which sections dependent on loaders or actions should render synchronously with the page.

### Proposal
To address these issues, we propose an Async Render Default approach, which involves the following steps:

1. Default Asynchronous Rendering: By default, defer the rendering of all sections via the deco.cx admin. This ensures optimized performance across the board.
1. Opt-out Option: Users can choose to opt-out of this default behavior by disabling the optimization property on individual section forms within the page.
2.
Optimized sections will be wrapped in a mechanism that renders a fallback initially and then fetches the full section content when the page loads in the browser. This approach aims to enhance overall page performance and user experience by leveraging efficient caching and load times.