add filament source persistence, palette3 boolean in preview/export

src/mode/fdm/export.js

@@ -119,7 +119,8 @@
             icos = 1 / bcos,
             inloops = 0,
             arcQ = [],
-            minz = { x: Infinity, y: Infinity, z: Infinity };
+            minz = { x: Infinity, y: Infinity, z: Infinity },
+            isPalette = device.filamentSource === 'palette3';
 
         // smallish band-aid. refactor above to remove redundancy
         function updateParams(layer) {

src/mode/fdm/prepare.js

@@ -34,6 +34,7 @@
             isThin = controller.lineType === "line",
             isFlat = controller.lineType === "flat",
             isDanger = controller.danger || false,
+            isPalette = device.filamentSource === 'palette3',
             firstLayerHeight = isBelt ? process.sliceHeight : process.firstSliceHeight || process.sliceHeight,
             firstLayerSeek = process.outputSeekrate,
             firstLayerRate = process.firstLayerRate,