完善中央与边缘部署、远程写入与监控文档

- 增加中央与边缘完整配置和部署脚本
- 引入 VictoriaMetrics 数据源与 remote_write 故障排查说明
- 新增 edge-agent 配置脚本、ONVIF 自建 exporter 与 ping 监控示例

Co-authored-by: Cursor <cursoragent@cursor.com>

central-server/grafana/dashboards/onvif-monitoring.json

@@ -0,0 +1,76 @@
+{
+  "dashboard": {
+    "id": null,
+    "title": "ONVIF设备监控",
+    "tags": ["onvif", "camera", "monitoring"],
+    "style": "dark",
+    "timezone": "browser",
+    "panels": [
+      {
+        "id": 1,
+        "title": "ONVIF设备状态",
+        "type": "stat",
+        "targets": [
+          {
+            "expr": "up{job=\"onvif-devices\"}",
+            "refId": "A"
+          }
+        ],
+        "fieldConfig": {
+          "defaults": {
+            "color": {
+              "mode": "thresholds"
+            },
+            "thresholds": {
+              "steps": [
+                {
+                  "color": "red",
+                  "value": 0
+                },
+                {
+                  "color": "green",
+                  "value": 1
+                }
+              ]
+            }
+          }
+        },
+        "gridPos": {
+          "h": 8,
+          "w": 12,
+          "x": 0,
+          "y": 0
+        }
+      },
+      {
+        "id": 2,
+        "title": "设备在线率",
+        "type": "gauge",
+        "targets": [
+          {
+            "expr": "sum(up{job=\"onvif-devices\"}) / count(up{job=\"onvif-devices\"}) * 100",
+            "refId": "A"
+          }
+        ],
+        "fieldConfig": {
+          "defaults": {
+            "min": 0,
+            "max": 100,
+            "unit": "percent"
+          }
+        },
+        "gridPos": {
+          "h": 8,
+          "w": 12,
+          "x": 12,
+          "y": 0
+        }
+      }
+    ],
+    "time": {
+      "from": "now-1h",
+      "to": "now"
+    },
+    "refresh": "30s"
+  }
+}