fix: skip jimp processing for SVGs and prevent image-fill collapse (#298)

* fix: skip jimp processing for SVGs and prevent image-fill collapse

Two fixes:

1. SVGs are vector files that jimp can't parse. Skip dimension detection
   and cropping for SVG downloads — just save the file. Previously this
   crashed with "Could not find MIME for Buffer".

2. The SVG container collapse logic was swallowing frames that contain
   image fills. A carousel with 4 image-filled children would cascade-
   collapse into a single IMAGE-SVG node, losing all child structure.
   Now checks for image fills in the subtree before collapsing.

* perf: check only direct children for image fills during SVG collapse

afterChildren runs bottom-up, so if a deeper descendant has image fills,
its parent won't collapse and stays FRAME—which isn't SVG-eligible,
naturally breaking the cascade. No need to walk the full subtree.

Author: GLips

src/extractors/built-in.ts

@@ -239,7 +239,8 @@ export function collapseSvgContainers(
 
   if (
     (node.type === "FRAME" || node.type === "GROUP" || node.type === "INSTANCE") &&
-    allChildrenAreSvgEligible
+    allChildrenAreSvgEligible &&
+    !hasImageFillInChildren(node)
   ) {
     // Collapse to IMAGE-SVG and omit children
     result.type = "IMAGE-SVG";
@@ -249,3 +250,22 @@ export function collapseSvgContainers(
   // Include all children normally
   return children;
 }
+
+/**
+ * Check whether a node or its direct children have image fills.
+ *
+ * Only direct children need checking because afterChildren runs bottom-up:
+ * if a deeper descendant has image fills, its parent won't collapse (stays FRAME),
+ * and FRAME isn't SVG-eligible, so the chain breaks naturally at each level.
+ */
+function hasImageFillInChildren(node: FigmaDocumentNode): boolean {
+  if (hasValue("fills", node) && node.fills.some((fill) => fill.type === "IMAGE")) {
+    return true;
+  }
+  if (hasValue("children", node)) {
+    return node.children.some(
+      (child) => hasValue("fills", child) && child.fills.some((fill) => fill.type === "IMAGE"),
+    );
+  }
+  return false;
+}

src/utils/image-processing.ts

@@ -105,6 +105,18 @@ export async function downloadAndProcessImage(
   const originalPath = await downloadFigmaImage(fileName, localPath, imageUrl);
   Logger.log(`Downloaded original image: ${originalPath}`);
 
+  // SVGs are vector — jimp can't read them and cropping/dimensions don't apply
+  const isSvg = fileName.toLowerCase().endsWith(".svg");
+  if (isSvg) {
+    return {
+      filePath: originalPath,
+      originalDimensions: { width: 0, height: 0 },
+      finalDimensions: { width: 0, height: 0 },
+      wasCropped: false,
+      processingLog,
+    };
+  }
+
   // Get original dimensions before any processing
   const originalDimensions = await getImageDimensions(originalPath);
   Logger.log(`Original dimensions: ${originalDimensions.width}x${originalDimensions.height}`);