Support user-generated RFQ on `tchrpc.SendPayment` #3510

Job	Run time
cross compilation	4m 33s
Format check	20s
Docker build check	3m 42s
Compilation check	46s
run itests	9m 41s
run itests postgres	17m 42s
Lint check	2m 34s
migration version check	15s
go mod check	25s
RPC check	1m 15s
run LiT tests	12m 27s
sample configuration check	41s
Sqlc check	34s
test vector check	45s
run unit tests (unit-race)	11m 18s
run unit tests (unit-cover)	3m 0s
run unit tests (unit dbbackend=postgres)	5m 52s
finish	5s
	1h 15m 55s

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