Support user-generated RFQ on `tchrpc.SendPayment` #3531

Job	Run time
Format check	21s
Docker build check	3m 37s
Compilation check	1m 32s
cross compilation	11m 59s
run itests	11m 23s
run itests postgres	19m 49s
Lint check	2m 34s
migration version check	11s
go mod check	21s
RPC check	1m 9s
run LiT tests	9m 42s
sample configuration check	41s
Sqlc check	37s
test vector check	55s
run unit tests (unit-race)	11m 11s
run unit tests (unit-cover)	4m 35s
run unit tests (unit dbbackend=postgres)	5m 54s
finish	2s
	1h 26m 33s

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