chore: add BMAD workflow commands for Claude and Cursor

Include .claude/commands/ and .cursor/commands/ containing all BMAD
workflow definitions so team members can use them out of the box.
Only .claude/settings.local.json remains gitignored (user-specific).

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

.gitignore

@@ -26,6 +26,5 @@ yarn-error.log
 /.nova
 /.vscode
 /.zed
-/.claude
-/.cursor
+/.claude/settings.local.json
 /.windsurf