fix(ci): build native node images and add compose files [CI]

Restore with PublishAot so agent and probe images contain NativeAOT
binaries instead of a launcher that needs a .dll, fail the build when the
binary is too small, add agent and probe compose files, and document the
[CI] marker in AGENTS.md.

packaging/compose/agent/compose.yaml

@@ -0,0 +1,33 @@
+# Agent：配置和身份都放在同目录的 .data/（挂载到容器的 /etc/monitor）。
+#
+# 第一次使用：
+#   mkdir -p .data && sudo chown 1654:1654 .data        # 容器以 UID/GID 1654 运行
+#   MONITOR_JOIN_TOKEN=<加入令牌> MONITOR_SERVER=https://<backend> MONITOR_AGENT_NAME=<名字> \
+#     docker compose run --rm --entrypoint /usr/local/bin/fleet-enroll agent \
+#     --server "$MONITOR_SERVER" --join "$MONITOR_JOIN_TOKEN" --name "$MONITOR_AGENT_NAME" --identity-dir /etc/monitor/agent-id
+#   再在 .data/agent.json 里写（fleet.identity_dir 要和上面一致）：
+#   {"fleet":{"server":"https://<backend>","identity_dir":"/etc/monitor/agent-id"},"listen":{"bind":"0.0.0.0"},"limits":{"max_total_mbps":100,"max_total_pps":10000}}
+#   docker compose up -d
+#
+# 更新：改 MONITOR_VERSION（或 MONITOR_IMAGE），再 docker compose pull && docker compose up -d。.data 不动，身份和历史都保留。
+services:
+  agent:
+    image: ${MONITOR_IMAGE:-registry.oeo.one/monitor/monitor-agent}:${MONITOR_VERSION:-0.1.1}
+    container_name: monitor-agent
+    restart: unless-stopped
+    init: true
+    # Probe 要直连 Agent 的 7443（TCP+UDP）和 7444（TCP），用宿主网络，不做端口映射
+    network_mode: host
+    volumes:
+      - ./.data:/etc/monitor
+    read_only: true
+    tmpfs:
+      - /tmp:rw,noexec,nosuid,size=64m,mode=1777
+    security_opt:
+      - no-new-privileges:true
+    cap_drop:
+      - ALL
+    # 要做 ICMP 测量时打开：
+    # cap_add:
+    #   - NET_RAW
+    stop_grace_period: 20s