[Feature Request] Add an Aggregated Dashboard View for Multiple Websites

[theAlevan]

Describe the feature or enhancement

Currently, Umami displays each tracked website individually on the main dashboard, making it difficult to quickly see the overall performance of multiple sites.

I propose adding an option for an aggregated view on the main dashboard that combines key statistics (e.g., total visitors, pageviews, visits) from all tracked websites into a single summary. This would provide a quick, centralized overview for users managing multiple sites, improving efficiency and making it easier to monitor overall traffic and trends at a glance.

[mikecao]

We have something like this planned.