chanmon_consistency: add tests verifying force-close fuzzer actions

Add tests that exercise the new force-close fuzzer byte actions and verify
they produce the expected behavior by asserting on specific log messages.

Tests cover: basic force-close lifecycle, negative case without chain
advancement, bidirectional force-close, middle node initiating, HTLC
timeout delay, HTLC resolution after height advance, and a three-node
scenario where A force-closes during fulfill propagation and learns the
preimage on-chain from B's HTLC claim.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: joostjager