fix gitignore: .claude/worktrees not .claude/workstrees

The previous commit had a typo (workstrees) so the directory was not
actually ignored. Also adds a trailing newline.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Signed-off-by: Douglas Strodtman <douglas@anyscale.com>

Author: dstrodtman

.gitignore

@@ -253,4 +253,4 @@ CLAUDE.local.md
 
 # Worktrees
 .worktrees/
-.claude/workstrees/
+.claude/worktrees/