Project VSD - Expose usage overview metrics

Background

The Usage overview panel is currently available on the group and subgroup levels. But we would like to expose this for project namespaces also.

TODO

On the backend we should expose a similar GraphQL query to support usage data at the project level

Supported metrics at the project level:

• issues
• pipelines
• merge requests
• members (this is possible to implement, it's not available at the moment)

Some code reuse might happen on the backend with the Resolvers::Analytics::ValueStreamDashboard::CountResolver class. We need to provide a different enum for the metric list: Types::Analytics::ValueStreamDashboard::MetricEnum. This enum includes metrics which would not be supported on the project-level.