Add more information when a co-op close is failing.

[ziggie1984]

Change Description

Resulting from discussions in the noderunner group where someone could not co-op close a channel but was not able to understand why:

Logs where only showing:

==> /var/log/syslog <==
Oct 10 13:21:09 lnd[1591]: 2023-10-10 13:21:09.933 [INF] PEER: Peer(xxx): Local close channel request delivered to peer
==> /home/bitcoin/.lnd/logs/bitcoin/mainnet/lnd.log <==2023-10-10 13:21:09.950 [ERR] PEER: Peer(xxx): failed link shutdown: link failed to shutdown

This had the appearance that the peer somehow was not willing to cooperate ("request delivered to peer"), now we give the user better feedback what's happening.

Now would be:

2023-10-12 11:22:08.349 [INF] PEER: Peer(0355402a07589a522375f83b6f6c42c4144d219ec3810e0a2aefb8ae99bdabd095): Local close channel request is going to be delivered to the peer
2023-10-12 11:22:08.367 [INF] PEER: Peer(0355402a07589a522375f83b6f6c42c4144d219ec3810e0a2aefb8ae99bdabd095): Delivery addr for channel close: bcrt1p2szcuwgt3dzkf5awkw27xzjrshf6vdsrx0y5sqj67w6flueh0pwqelcxp2
2023-10-12 11:22:08.367 [INF] HSWC: ChannelLink(877b1cd70661da033ab740928b6d0ca9ee6dcf023859f8f38e1381d45b036efc:0): Channel is in an unclean state (lingering updates), graceful shutdown of channel link not possible
2023-10-12 11:22:08.367 [ERR] PEER: Peer(0355402a07589a522375f83b6f6c42c4144d219ec3810e0a2aefb8ae99bdabd095): failed link shutdown: link failed to shutdown

And for the receiver:
[lncli] rpc error: code = Unknown desc = failed handling co-op closing request with (try force closing it instead): link failed to shutdown

[yyforyongyu]

Nice addition! Could you remove the skip ci flag and let the build run? Think we wanna disable this flag as previously we've had changes we thought were small enough to skip the CI while they turned out to violate the linters.

[yyforyongyu]

LGTM🙏

[guggero]

LGTM 🎉