BN Map is incorrectly generated

It seems that the BN is creating its own `/map` by aggregating the maps from the different beacon members.
However, this makes the BN map unstable as it depends on the beacons available (responding) at a given moment.
We created a mock endpoint "`/gVariants2`" and the BN picked it as its own genomicVariations endpoint.
I believe that the BN should have its own map and redirect the calls to the corresponding endpoints in the beacons.

Start by tracing how the BN generates `/map` from beacon members and how it selects the `/gVariants2` endpoint. Determine how the BN can keep its own stable map while redirecting requests to the corresponding beacon endpoints. Done means the BN map no longer changes with beacon availability and calls reach the intended endpoints.

Written by the indexing model from the issue text.