Ablative config

src/pages/Solver.jsx

@@ -22,10 +22,13 @@ export default function Solver() {
     getUnit,
     setUnit,
     sciNotation,
+    areaRatioBranch,
     toggleSciNotation,
+    toggleAreaRatioBranch,
     addVariable,
     addVariables,
     removeVariable,
+    reorderVariable,
     setValue,
     addPreset,
     applyPropellant,
@@ -48,10 +51,20 @@ export default function Solver() {
 
   function handleDragEnd(event) {
     const { over, active } = event
-    if (over?.id === 'workspace') {
+    if (!over) {
+      setActiveVarId(null)
+      return
+    }
+
+    // Palette → workspace drop
+    if (over.id === 'workspace') {
       const { varId } = active.data.current ?? {}
       if (varId) addVariable(varId)
     }
+    // Workspace → workspace reorder
+    else if (workspaceVarIds.includes(active.id) && workspaceVarIds.includes(over.id)) {
+      reorderVariable(active.id, over.id)
+    }
     setActiveVarId(null)
   }
 
@@ -128,6 +141,8 @@ export default function Solver() {
             getUnit={getUnit}
             setUnit={setUnit}
             sciNotation={sciNotation}
+            areaRatioBranch={areaRatioBranch}
+            onToggleAreaRatioBranch={toggleAreaRatioBranch}
           />
           <ResultsPanel
             workspaceVarIds={workspaceVarIds}
@@ -147,7 +162,6 @@ export default function Solver() {
         <PropellantModal
           onClose={() => setShowPropellants(false)}
           onApply={applyPropellant}
-          existingVarIds={workspaceVarIds}
         />
       )}