[perf-dash] Perf-dash should automatically pick up new measurements

Perf-dash should automatically pick up new measurements if they are plain, simple and don't require extra processing (e.g. aggregations or grouping).

Profit: adding and displaying new measurements would be easier.

/area perf-dash

Start by locating the perf-dash implementation and how it currently discovers measurements. Check how plain measurements are represented and where aggregation or grouping is required. Done means newly added simple measurements are discovered and displayed automatically without extra processing.

Written by the indexing model from the issue text.