Provide a "real" dashboard with multi-project reporting, status and checks

### Describe the problem

We need to monitor a large set of projects and want to provide translators and reviewer with critical information like unreviewed strings, new strings since the last login. This is not possible with the current dashboard in Weblate.

### Solution brainstorm

Configurable dashboards for teams where work-related information can be dsiplayed in a user-friendly style, within a defined project cluster and for a given language, e.g.
- List of unreviewed, changed and empty strings, that can be sorted and filtered
- Number of unreviewed strings
- List of critical checks, e.g. Python format, Python brace format
- Standard and individual search queries

### Describe alternatives you have considered

I looked into component lists, categories. But these are all not very user-friendly and quite limited.

### Screenshots

_No response_

### Additional context

_No response_