Channel/CommitmentsModule: avoid hardcoding values

This code assumes that the person who broadcasted
the commitment transaction is always the funder and
the person who is trying to spend the broadcasted
remote commitment is always the fundee.
This passed geewallet CI tests because that's
the only case we test in geewallet end-to-end tests.

Author: aarani

src/DotNetLightning.Core/Channel/CommitmentsModule.fs

@@ -559,7 +559,7 @@ module RemoteForceClose =
         let remoteChannelPubKeys = commitments.RemoteParams.ChannelPubKeys
         let commitmentNumber =
             obscuredCommitmentNumber.Unobscure
-                false
+                commitments.LocalParams.IsFunder
                 localChannelPubKeys.PaymentBasepoint
                 remoteChannelPubKeys.PaymentBasepoint
         let perCommitmentSecretOpt =
@@ -643,7 +643,7 @@ module RemoteForceClose =
         let remoteChannelPubKeys = commitments.RemoteParams.ChannelPubKeys
         let commitmentNumber =
             obscuredCommitmentNumber.Unobscure
-                true
+                commitments.LocalParams.IsFunder
                 localChannelPubKeys.PaymentBasepoint
                 remoteChannelPubKeys.PaymentBasepoint