lnwallet+contractcourt: gracefully handle auto force close post data loss

In this commit, update the start up logic to gracefully handle a
seemingly rare case. In this case, a peer detects local data loss with a
set of active HTLCs. These HTLCs then eventually expire (they may or may
not actually "exist"), causing a force close decision. Before this PR,
this attempt would fail with a fatal error that can impede start up.

To better handle such a scenario, we'll now catch the error when we fail
to force close due to entering the DLP and instead terminate the state
machine at the broadcast state. When a commitment transaction eventually
confirms, we'll play it as normal.

Fixes https://github.com/lightningnetwork/lnd/issues/7984

docs/release-notes/release-notes-0.17.0.md

@@ -71,6 +71,10 @@ fails](https://github.com/lightningnetwork/lnd/pull/7876).
   retried](https://github.com/lightningnetwork/lnd/pull/7927) with an
   exponential back off.
 
+* `lnd` [now properly handles a case where an erroneous force close attempt
+  would impeded start up](https://github.com/lightningnetwork/lnd/pull/7985).
+
+
 # New Features
 ## Functional Enhancements
 ### Protocol Features