T06: named-combos editor gains a @dnd-kit/sortable drag-to-reorder stacked pipeline backed by a pure model (compressionPipelineModel.ts: add/remove/move/update, engine->intensity invariant, never-empty). CompressionPipelineEditor.tsx replaces the inline fixed list in CompressionCombosPageClient; order persists via the existing combos endpoint (no API change). T03: adds tests/e2e/compression-studio.spec.ts (Tela A render + Play/Compare tab switch), the dedicated compression-studio e2e combo-live-studio.spec.ts did not cover. TDD: compression-pipeline-model.test.ts (11) + compression-pipeline-editor.test.tsx (4). gaps v3.8.42 — T06 + T03.