Return one flow's graph topology: its blocks in reading order from the start block, a short summary per block, and where each block and each menu button leads (links[].to, menu.buttons[].to). Read-only. Deliberately omits block data, action configs and the ids of buttons, actions, links and condition rules to stay cheap, and returns message text and condition operands only as cut *Preview fields (textPreview, firstOperandPreview, valuePreview) that are for reading, never for writing back — once you know which block matters, call get_block_details for its full contents. This is the normal first step before editing an existing flow.