chore: add .claude/ to gitignore and remove from index

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: braboj

.claude/worktrees/agent-abc53eb2

@@ -26,6 +26,9 @@ dist/
 # JetBrains IDE
 .idea/
 
+# Claude Code
+.claude/
+
 # Unit test reports
 TEST*.xml