Define rules on how DCP names should be constructed

Bug/improvement...

KV currently creates "connection-type" DCP statistics, where the connection-type is inferred by splitting the connection name with a ":", for example we end up with item's remaining stats with connection level labels such as

• replication
• fts
• eventing

Which is very useful for inspecting how each DCP client is behaving.

However, cbbackupmgr uses a name such as

• cbbackupmgr_2023-06-23T09:00:28-05:00_64003_0

Which leads to a label cbbackupmgr_2023-06-23T09 and then we see problems when plotting as per the attached screen shot.

Overall this is is a KV issue as we just split the name as given and there are no rules as to how a DCP name should be constructed, so we can certainly change cbbackupmgr, but another client can just cause a problem...