Rust projects in the workspace need a C linker (cc).

Assisted-by: Claude Opus 4.6 via pi

diff --git a/assets/Dockerfile b/assets/Dockerfile
index 6ceb21a..2f19b14 100644
--- a/assets/Dockerfile
+++ b/assets/Dockerfile
@@ -3,6 +3,7 @@ FROM node:24-trixie-slim
 ARG TARGETARCH
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
+    build-essential \
     ca-certificates \
     curl \
     fd-find \