fix(images): bound external runtime processing

src/server/images/processing.ts

@@ -177,10 +177,11 @@ export async function processSignageImage(bytes: Uint8Array): Promise<SignagePro
     height: metadata.height as number,
     width: metadata.width as number,
   };
-  const [display, thumbnail] = await Promise.all([
-    renderRendition(bytes, SIGNAGE_IMAGE_DISPLAY_RENDITION),
-    renderRendition(bytes, SIGNAGE_IMAGE_THUMBNAIL_RENDITION),
-  ]);
+  // Keep peak native CPU and memory bounded inside the shared API process. Upload concurrency is
+  // already bounded at the module UI; running both renditions for every upload in parallel would
+  // multiply that concurrency again and can starve the database and storage clients on a small host.
+  const display = await renderRendition(bytes, SIGNAGE_IMAGE_DISPLAY_RENDITION);
+  const thumbnail = await renderRendition(bytes, SIGNAGE_IMAGE_THUMBNAIL_RENDITION);
 
   return {
     byteSize: bytes.byteLength,