fix: aggregate large ink groups safely

src/onenote/one/content.ts

@@ -623,7 +623,7 @@ function parseInk(
       id: exGuidKey(object.id),
       strokes: [],
       children,
-      boundingBox: unionBoundingBoxes(
+      boundingBox: unionInkBoundingBoxes(
         children.map((child) => child.boundingBox)
       ),
       layout: parseLayout(object),
@@ -915,18 +915,24 @@ function boundingBoxFromStrokes(
     : undefined;
 }
 
-function unionBoundingBoxes(
+/** @internal Exported so the bounded aggregation path can be stress-tested. */
+export function unionInkBoundingBoxes(
   boxes: readonly (OneNoteInkBoundingBox | undefined)[]
 ): OneNoteInkBoundingBox | undefined {
-  const present = boxes.filter(
-    (box): box is OneNoteInkBoundingBox => box !== undefined
-  );
-  if (present.length === 0) return undefined;
-  const x = Math.min(...present.map((box) => box.x));
-  const y = Math.min(...present.map((box) => box.y));
-  const x2 = Math.max(...present.map((box) => box.x + box.width));
-  const y2 = Math.max(...present.map((box) => box.y + box.height));
-  return { x, y, width: x2 - x, height: y2 - y };
+  let x = Infinity;
+  let y = Infinity;
+  let x2 = -Infinity;
+  let y2 = -Infinity;
+  for (const box of boxes) {
+    if (!box) continue;
+    x = Math.min(x, box.x);
+    y = Math.min(y, box.y);
+    x2 = Math.max(x2, box.x + box.width);
+    y2 = Math.max(y2, box.y + box.height);
+  }
+  return Number.isFinite(x)
+    ? { x, y, width: x2 - x, height: y2 - y }
+    : undefined;
 }
 
 function parseLayout(object: StoreObject): OneNoteLayout {