RFQ session lookup during quote accept message parsing

[ffranr]

This PR is not a breaking change. It's related to #871

Future RFQ quote accept messages will not contain enough information for the RFQ service to classify them as buy or sell. Therefore, before these messages can be fully interpreted, the corresponding quote request message must be retrieved and inspected.

This commit modifies the parsing of incoming quote accept messages so they can be accurately classified as buy or sell by looking up the associated quote request message.

As a beneficial side effect, parsed quote accept message fields are now fully populated within the parsing routine.

[coveralls]

Pull Request Test Coverage Report for Build 10941878808

Details

• 0 of 56 (0.0%) changed or added relevant lines in 8 files are covered.
• 15 unchanged lines in 6 files lost coverage.
• Overall coverage increased (+0.03%) to 40.422%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
rfqmsg/buy_accept.go	0	2	0.0%
rfqmsg/sell_accept.go	0	2	0.0%
rfqmsg/messages.go	0	3	0.0%
rfqmsg/buy_request.go	0	6	0.0%
rfqmsg/reject.go	0	6	0.0%
rfqmsg/sell_request.go	0	6	0.0%
rfq/stream.go	0	13	0.0%
rfqmsg/accept.go	0	18	0.0%

Files with Coverage Reduction	New Missed Lines	%
rfqmsg/accept.go	1	37.35%
internal/test/helpers.go	2	86.85%
tappsbt/create.go	2	53.22%
commitment/tap.go	2	84.43%
tapgarden/caretaker.go	4	68.5%
asset/asset.go	4	81.61%

Totals
Change from base Build 10941480416:	0.03%
Covered Lines:	24223
Relevant Lines:	59925

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💛 - Coveralls

[guggero]

Nice refactor! Will come in handy with the following RFQ message changes, I'm sure.

[GeorgeTsagk]

✨