Fix typo

Editor assessment

The subject `docs: fix typo` names the change class but no file, page, or word, so the location is only recoverable from the body's bullets referencing the illustration docs. The docs type is correct for the edit. The body squash bullets — updates to the Chinese and English illustration files — supply the missing where, but no description of the typo itself. No footer appears. Hygiene is clean in form. Understandable once both lines are read, yet the headline alone fails to locate the change for a reader.