chore: add daemon-error to .gitignore

The daemon-error file is a transient runtime file created when the daemon
fails to start. It should not be tracked in git.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

.gitignore

@@ -41,6 +41,7 @@ Thumbs.db
 .beads/daemon.log
 .beads/daemon.pid
 .beads/daemon.lock
+.beads/daemon-error
 .beads/bd.sock
 .beads/.exclusive-lock