[Docs](memory) fix document directory and fix memtracker accuracy bug (#14710)

docs/dev.json

@@ -259,6 +259,10 @@
     "message": "监控指标",
     "description": "The label for category Monitor Metrics in sidebar docs"
   },
+  "sidebar.docs.category.Memory Management": {
+    "message": "内存管理",
+    "description": "The label for category Memory Management in sidebar docs"
+  },
   "sidebar.docs.category.Config": {
     "message": "配置管理",
     "description": "The label for category Config in sidebar docs"

docs/sidebars.json

@@ -1019,6 +1019,15 @@
                         "admin-manual/maint-monitor/metadata-operation"
                     ]
                 },
+                {
+                    "type": "category",
+                    "label": "Memory Management",
+                    "items": [
+                        "admin-manual/maint-monitor/memory-management/memory-tracker",
+                        "admin-manual/maint-monitor/memory-management/memory-limit-exceeded-analysis",
+                        "admin-manual/maint-monitor/memory-management/be-oom-analysis"
+                    ]
+                },
                 {
                     "type": "category",
                     "label": "Config",