tapcfg: allow using mainnet, enable universe proof courier by default #1600

Job	Run time
go mod check	1m 24s
cross compilation	13m 9s
Lint check	3m 41s
Docker build check	4m 6s
Compilation check	37s
RPC check	1m 41s
Sqlc check	24s
test vector check	1m 28s
Format check	37s
run itests	8m 3s
run itests postgres	12m 28s
run unit tests (unit-race)	6m 56s
run unit tests (unit-cover)	4m 56s
run unit tests (unit dbbackend=postgres)	5m 14s
	1h 4m 44s

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