fix dockerfile

mindforge.cronjob/Dockerfile

@@ -8,9 +8,11 @@ ARG TARGETOS
 RUN apk --no-cache add ca-certificates
 
 WORKDIR /app
+COPY go.mod go.sum ./
+RUN go mod download
 COPY . .
 # Build statically for Linux
-RUN CGO_ENABLED=0 GOOS=${TARGETOS} GOARCH=${TARGETARCH} go build -o mindforge-cronjob main.go
+RUN CGO_ENABLED=0 GOOS=${TARGETOS} GOARCH=${TARGETARCH} go build -o mindforge-cronjob ./cmd/mindforge.cronjob
 
 # Use scratch to avoid QEMU: no foreign-arch commands to emulate
 FROM scratch