[Feat.Req] Primary and backup configs

Request from VInce (Data Nexus) on Discord (https://discord.com/channels/438038660412342282/1087503343410225152/1260662322964201614):

>Can we get a primary and backup configs for registry and network subgraphs? I'd like to use my internal query node URL to save on query fees, but I don't want my subgraph radio to stop working if I fall behind.