Fix Dockerfile: add curl, remove optional copy

Dockerfile

@@ -7,8 +7,7 @@ FROM golang:1.22-bookworm AS builder
 WORKDIR /build
 
 # Copy go module files first for better caching
-COPY go.mod go.sum* ./
-RUN go mod download 2>/dev/null || true
+COPY go.mod ./
 
 # Copy source code
 COPY *.go ./
@@ -23,9 +22,9 @@ RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags="-w -s" -o curiosity
 # Stage 2: Runtime
 FROM debian:bookworm-slim
 
-# Install CA certificates for HTTPS
+# Install CA certificates and curl for HTTPS and health checks
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    ca-certificates \
+    ca-certificates curl \
     && rm -rf /var/lib/apt/lists/*
 
 # Create non-root user (HuggingFace Spaces requirement)
@@ -38,8 +37,8 @@ WORKDIR /app
 COPY --from=builder /build/curiosity-crawler /app/curiosity-crawler
 RUN chmod +x /app/curiosity-crawler
 
-# Copy W_know snapshot if available (will be downloaded on startup if not)
-COPY --chown=crawler:crawler w_know.bin* /app/data/ 2>/dev/null || true
+# W_know will be downloaded on startup from HuggingFace dataset
+# No need to copy it here - keeps the image small
 
 # Switch to non-root user
 USER crawler