diagramStem

File-stem convention used today by the convert task when naming .dot files (data_flow_summarized, control_flow_detailed_per_ir_instruction, etc.) — folds DiagramType + SummaryType into a single underscore-joined token.

For DiagramType.DATA_FLOW_DIAGRAM / DiagramType.CONTROL_FLOW_DIAGRAM the _diagram suffix is stripped (so the stem reads data_flow_summarized, not data_flow_diagram_summarized). DiagramType.COMBINED_DATA_AND_CONTROL_FLOW_DIAGRAM keeps its full folder name because there's no shorter conventional form.

The diagram-stem axis can be deleted entirely once the convert task switches to the 5-axis path scheme (the stem becomes redundant when (DiagramType, SummaryType) are encoded in the file's parent directory). Tracked in issue12-pipeline-cleanup.md.