fix: remove chmod /etc/hosts (read-only in build), run DNS sync before app

Removed chmod 666 /etc/hosts from Dockerfile (HF build filesystem is
read-only). Changed DNS resolution from background to blocking so
/tmp/dns-resolved.json and /etc/hosts entries are ready before OpenClaw
starts — needed for undici/fetch which bypasses dns.lookup patching.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Dockerfile

@@ -14,7 +14,6 @@ RUN echo "[build][layer1] System deps + tools..." && START=$(date +%s) \
   && chown node:node /app \
   && mkdir -p /home/node/.openclaw/workspace /home/node/.openclaw/credentials \
   && chown -R node:node /home/node \
-  && chmod 666 /etc/hosts \
   && echo "[build][layer1] System deps + tools: $(($(date +%s) - START))s"
 
 # ── 切换到 node 用户（后续所有操作都以 node 身份，无需 chown）───────────────

scripts/entrypoint.sh

@@ -6,15 +6,12 @@ BOOT_START=$(date +%s)
 echo "[entrypoint] OpenClaw HuggingFace Spaces Entrypoint"
 echo "[entrypoint] ======================================="
 
-# ── DNS pre-resolution (run in BACKGROUND — was 121s blocking) ──────────────
-echo "[entrypoint] Resolving WhatsApp & Telegram domains via DNS-over-HTTPS (background)..."
+# ── DNS pre-resolution (BLOCKING — needed before app starts) ──────────────
+echo "[entrypoint] Resolving WhatsApp & Telegram domains via DNS-over-HTTPS..."
 DNS_START=$(date +%s)
-(
-  python3 /home/node/scripts/dns-resolve.py /tmp/dns-resolved.json 2>&1
-  DNS_END=$(date +%s)
-  echo "[TIMER] DNS pre-resolve (background): $((DNS_END - DNS_START))s"
-) &
-DNS_PID=$!
+python3 /home/node/scripts/dns-resolve.py /tmp/dns-resolved.json 2>&1
+DNS_END=$(date +%s)
+echo "[TIMER] DNS pre-resolve: $((DNS_END - DNS_START))s"
 
 # ── Node.js memory limit (only if explicitly set) ─────────────────────────
 if [ -n "$NODE_MEMORY_LIMIT" ]; then
@@ -60,7 +57,6 @@ if [ -f /app/openclaw/.version ]; then
   echo "[entrypoint] OpenClaw version: $OPENCLAW_VERSION"
 fi
 
-# ── Start OpenClaw via sync_hf.py (don't wait for DNS — it runs in bg) ─────
+# ── Start OpenClaw via sync_hf.py ─────────────────────────────────────────
 echo "[entrypoint] Starting OpenClaw via sync_hf.py..."
-echo "[entrypoint] DNS resolution running in background (PID $DNS_PID), app will use it when ready"
 exec python3 -u /home/node/scripts/sync_hf.py