        d=Document(f/'source.docx');p=d.paragraphs[0];replace_cross_runs(p,'{{CUSTOMER}}',str(output.get('customer','')));d.save(f/'filled.docx');p=Document(f/'filled.docx').paragraphs[0];ck('变量替换使用模型字段',p.text=='Dear 星海实验室 — approved.');ck('非目标前缀粗体不变',p.runs[0].bold is True);ck('非目标后缀斜体不变',p.runs[-1].italic is True);ck('没有残留跨run变量','{{' not in p.text);result={'text':p.text,'runs':[{'text':r.text,'bold':r.bold,'italic':r.italic} for r in p.runs]};add_native(f/'filled.docx')
