[feature]: RFQ service registers quote SCID with LND SCID alias manager

[ffranr]

This issue relates to the addition of a Short Channel ID (SCID) alias manager to LND, as discussed in Issue #8199.

Objective

After the above-mentioned issue is merged, our next step will involve updating our code to ensure that the tapd RFQ service registers a custom SCID with LND.

Details

The integration should function as follows:

• The tapd RFQ layer will, upon agreeing to a quote, register the custom quote specific SCID with the new LND SCID alias RPCs.
• This will inform LND that any HTLC forward requests containing the special rfq_scid should not be automatically rejected.

[ffranr]

Completing this issue might not be necessary in order to get our channel payment PoC working. LND doesn't seem to reject the SCID if we use invoice hop hints. We have an itest that uses hop hints to this effect.

[dstadulis]

this issue might not be possible

did you mean necessary?

[dstadulis]

Should this issue be closed @ffranr ?

[ffranr]

This work was completed as part of the tap channel proof-of-concept. It isn't in main yet. But I think we can close this now as it's included in merging work.