feat(BackupX): harden agent cluster backup workflow

Squash merge PR #61

server/internal/installscript/templates/agent-install.sh.tmpl

@@ -109,7 +109,20 @@ docker rm -f backupx-agent >/dev/null 2>&1 || true
 docker run -d --name backupx-agent --restart=unless-stopped \
     -e "BACKUPX_AGENT_MASTER=${MASTER_URL}" \
     -e "BACKUPX_AGENT_TOKEN=${AGENT_TOKEN}" \
+    -e "BACKUPX_AGENT_TEMP_DIR=/var/lib/backupx-agent/tmp" \
     -v /var/lib/backupx-agent:/var/lib/backupx-agent \
     "awuqing/backupx:${AGENT_VERSION}" agent
-echo "✓ 容器已启动"
+echo "✓ 容器已启动，等待节点上线"
+for i in $(seq 1 15); do
+    sleep 2
+    if curl -fsSL -H "X-Agent-Token: ${AGENT_TOKEN}" "${MASTER_URL}/api/v1/agent/self" 2>/dev/null \
+        | grep -q '"status":"online"'; then
+        echo "✓ 节点已上线"
+        exit 0
+    fi
+done
+echo "⚠ 30s 内未收到上线心跳，请检查容器状态、网络与 Master URL。"
+echo "排查命令：docker ps -a --filter name=backupx-agent"
+echo "排查命令：docker logs --tail=100 backupx-agent"
+exit 2
 {{end}}