/** * Toggle header-row status on one or more table rows. * * This command sets **both** the cell node type (`tableHeader` ↔ `tableCell`) * and the OOXML repeat-header flag (`tableRowProperties.repeatHeader`) in a * single transaction so that undo reverts both changes atomically. * * ### Three distinct header concepts (do not conflate): * - **Repeat Header Row** — `tableRowProperties.repeatHeader` (OOXML `w:tblHeader`). * Controls whether the row repeats on continuation pages during pagination. * - **First Row Style Option** — `tableProperties.tblLook.firstRow`. * Controls conditional formatting from the table style. NOT set by this command. * - **Header Cell (`