fix: generate go.work in Dockerfile instead of copying gitignored file

build/Dockerfile.distro

@@ -10,9 +10,6 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 
 WORKDIR /build
 
-# Copy go.work first (lives in hive/)
-COPY hive/go.work ./hive/
-
 # Copy module files for dependency caching
 COPY hive/go.mod hive/go.sum ./hive/
 COPY predastore/go.mod predastore/go.sum ./predastore/
@@ -20,6 +17,9 @@ COPY viperblock/go.mod viperblock/go.sum ./viperblock/
 COPY viperblock/nbd/go.mod viperblock/nbd/go.sum ./viperblock/nbd/
 COPY viperblock/nbd/libguestfs.org/nbdkit/go.mod ./viperblock/nbd/libguestfs.org/nbdkit/
 
+# Generate go.work (gitignored, so not in checkout)
+RUN cd hive && go work init . ../predastore ../viperblock ../viperblock/nbd ../viperblock/nbd/libguestfs.org/nbdkit
+
 # Download dependencies (cached layer)
 RUN cd hive && go mod download