精简版第四轮补裁(P4): 页面层摘除 + Xray更新端点下线 + 本机核心监管下线

页面层(用户真机截图发现前两轮漏裁):
- 设置: 摘除 Telegram机器人/邮件菜单与页面, 及页内残留入口(通知页/外部流量/LDAP/2FA设置页)
- Xray配置: 摘除负载均衡/DNS/高级配置菜单与页面; 基础配置(出站+路由)完好
- 总览: 摘除 Xray更新弹窗(VersionModal+GeodataSection)全部入口, 版本号改为静态展示
- 13个locale同步摘除461个已删功能专属翻译键(逐键核查前后端引用为零; i18n-dead-keys测试全绿)

Xray更新后端(经调查确认仅服务本机bin/xray, 与agent下发/订阅无关):
- 删除 getXrayVersion/installXray/updateGeofile 路由与handler(访问返回404)
- 删除 ServerService 对应实现与校验和函数; 同步api-docs/monitor白名单/openapi

本机核心监管下线(设计: 主控永不运行本机xray, 入站全在agent):
- XrayService.RestartXray 降级为no-op(一次性Warning说明日志); StopXray无进程时幂等返回
- web.go 摘除启动拉起本机核心/CheckXrayRunning看门狗(1s)/ApplyPendingRestart cron(30s)/XrayTrafficJob/CheckClientIpJob 注册
- ApplyPendingRestart 降级为消费即清, 其测试更新为新语义
- XrayMetricsService.Sample 短路: 不再每2s探本机/debug/vars, 状态优雅置为不可用
- 配置生成(纯JSON)/agent链路/订阅/入站CRUD未动; 状态读数优雅归零(stop/Unknown)

注: TestGetXrayConfig_EnabledClientsStillEmitted 在基线945b3a5同样失败(既有问题, 非本轮引入)

frontend/public/openapi.json

@@ -5042,44 +5042,6 @@
         }
       }
     },
-    "/panel/api/server/getXrayVersion": {
-      "get": {
-        "tags": [
-          "Server"
-        ],
-        "summary": "List Xray binary versions available for install on this host.",
-        "operationId": "get_panel_api_server_getXrayVersion",
-        "responses": {
-          "200": {
-            "description": "Successful response",
-            "content": {
-              "application/json": {
-                "schema": {
-                  "type": "object",
-                  "properties": {
-                    "success": {
-                      "type": "boolean"
-                    },
-                    "msg": {
-                      "type": "string"
-                    },
-                    "obj": {}
-                  }
-                },
-                "example": {
-                  "success": true,
-                  "obj": [
-                    "v25.10.31",
-                    "v25.9.15",
-                    "v25.8.1"
-                  ]
-                }
-              }
-            }
-          }
-        }
-      }
-    },
     "/panel/api/server/getPanelUpdateInfo": {
       "get": {
         "tags": [
@@ -5613,47 +5575,6 @@
         }
       }
     },
-    "/panel/api/server/installXray/{version}": {
-      "post": {
-        "tags": [
-          "Server"
-        ],
-        "summary": "Download and install the specified Xray version. Pass \"latest\" for the newest release.",
-        "operationId": "post_panel_api_server_installXray_version",
-        "parameters": [
-          {
-            "name": "version",
-            "in": "path",
-            "required": true,
-            "description": "Xray tag (e.g. v25.10.31) or \"latest\".",
-            "schema": {
-              "type": "string"
-            }
-          }
-        ],
-        "responses": {
-          "200": {
-            "description": "Successful response",
-            "content": {
-              "application/json": {
-                "schema": {
-                  "type": "object",
-                  "properties": {
-                    "success": {
-                      "type": "boolean"
-                    },
-                    "msg": {
-                      "type": "string"
-                    },
-                    "obj": {}
-                  }
-                }
-              }
-            }
-          }
-        }
-      }
-    },
     "/panel/api/server/updatePanel": {
       "post": {
         "tags": [
@@ -5730,87 +5651,6 @@
         }
       }
     },
-    "/panel/api/server/updateGeofile": {
-      "post": {
-        "tags": [
-          "Server"
-        ],
-        "summary": "Refresh the default GeoIP / GeoSite data files. Body can include a fileName, or use the /:fileName variant.",
-        "operationId": "post_panel_api_server_updateGeofile",
-        "requestBody": {
-          "required": true,
-          "content": {
-            "application/json": {
-              "schema": {
-                "type": "object"
-              }
-            }
-          }
-        },
-        "responses": {
-          "200": {
-            "description": "Successful response",
-            "content": {
-              "application/json": {
-                "schema": {
-                  "type": "object",
-                  "properties": {
-                    "success": {
-                      "type": "boolean"
-                    },
-                    "msg": {
-                      "type": "string"
-                    },
-                    "obj": {}
-                  }
-                }
-              }
-            }
-          }
-        }
-      }
-    },
-    "/panel/api/server/updateGeofile/{fileName}": {
-      "post": {
-        "tags": [
-          "Server"
-        ],
-        "summary": "Refresh a single Geo file by filename (e.g. geoip.dat, geosite.dat).",
-        "operationId": "post_panel_api_server_updateGeofile_fileName",
-        "parameters": [
-          {
-            "name": "fileName",
-            "in": "path",
-            "required": true,
-            "description": "Filename of the data file to refresh.",
-            "schema": {
-              "type": "string"
-            }
-          }
-        ],
-        "responses": {
-          "200": {
-            "description": "Successful response",
-            "content": {
-              "application/json": {
-                "schema": {
-                  "type": "object",
-                  "properties": {
-                    "success": {
-                      "type": "boolean"
-                    },
-                    "msg": {
-                      "type": "string"
-                    },
-                    "obj": {}
-                  }
-                }
-              }
-            }
-          }
-        }
-      }
-    },
     "/panel/api/server/logs/{count}": {
       "post": {
         "tags": [