feat(admin): Flowcharts.vue JSON 在线编辑 + 9 套排查模板种子数据

为管理后台'排查流程图'模块加 JSON 在线编辑能力 + 提供 9 套
办公 IT 常见故障排查模板种子数据(账号/系统/企微/VPN/邮箱/网络/
打印机/软件/硬件),管理员可基于此学习、筛选、修改、新增。

## 选型(按'优选开源'原则)
- @codemirror/lang-json / state / theme-one-dark / view
- codemirror(核心)
- vue-codemirror(Vue 3 集成)
- vue-json-pretty(JSON 树形预览)
全部为社区成熟开源组件,非自行开发

## 改动
- frontend-admin/package.json: 加 6 个 npm 依赖
- frontend-admin/src/api/troubleshooting.ts(新): TS 类型 +
  5 个 API client(listTemplates / getTemplate / createTemplate /
  updateTemplate / deleteTemplate) + formatJson/validateJson/
  countNodes/countDecisions 工具函数
- frontend-admin/src/components/flowchart/FlowchartEditorDialog.vue(新):
  双面板编辑器(左 CodeMirror + 右 vue-json-pretty),
  实时 JSON 校验 + 节点/决策统计 + 格式/复制/导出按钮
- frontend-admin/src/views/Flowcharts.vue(改): 列表 + 导入/导出/
  新建按钮 + EditorDialog 集成 + 文件上传 + 删除确认

## 9 套种子数据
- 01-account-password.json 账号密码
- 02-pc-system.json        电脑系统
- 03-wecom.json            企微问题
- 04-vpn.json              VPN 接入
- 05-email.json            邮箱
- 06-network.json          网络
- 07-printer.json          打印机
- 08-software.json         软件
- 09-hardware.json         硬件
每套 ~150-200 行,结构:name / category / description /
estimated_time / difficulty / tags / root_node(决策树)

## 工具脚本
- data/seed-templates/build_all.py: 合并 9 个 JSON 成 00-all.json

data/seed-templates/01-account-password.json

@@ -0,0 +1,109 @@
+{
+  "name": "账号密码 / SSO 登录故障排查",
+  "category": "account",
+  "description": "员工忘记密码、账号被锁、SSO 单点登录失败、AD 域账号同步异常",
+  "estimated_time": 6,
+  "difficulty": 1,
+  "tags": ["账号", "密码", "SSO", "AD域", "登录"],
+  "root_node": {
+    "id": "fc-acct-1",
+    "type": "step",
+    "label": "确认员工使用哪种登录方式(域账号/企微SSO/邮箱SSO)",
+    "status": "pending",
+    "children": [
+      {
+        "id": "fc-acct-2",
+        "type": "decision",
+        "label": "是否提示账号已锁定?",
+        "yes_branch": {
+          "id": "fc-acct-3",
+          "type": "step",
+          "label": "AD 管理控制台解锁账号 + 重置临时密码",
+          "status": "pending",
+          "children": [
+            {
+              "id": "fc-acct-4",
+              "type": "step",
+              "label": "通知员工首次登录需修改密码",
+              "status": "pending"
+            },
+            {
+              "id": "fc-acct-5",
+              "type": "decision",
+              "label": "员工能正常登录?",
+              "yes_branch": {
+                "id": "fc-acct-6",
+                "type": "step",
+                "label": "回访确认 + 提醒密码保管"
+              },
+              "no_branch": {
+                "id": "fc-acct-7",
+                "type": "step",
+                "label": "升级二线:信息安全团队"
+              }
+            }
+          ]
+        },
+        "no_branch": {
+          "id": "fc-acct-8",
+          "type": "step",
+          "label": "确认密码是否过期(>90天)",
+          "status": "pending",
+          "children": [
+            {
+              "id": "fc-acct-9",
+              "type": "decision",
+              "label": "SSO 登录页能打开?",
+              "yes_branch": {
+                "id": "fc-acct-10",
+                "type": "step",
+                "label": "引导员工走自助密码重置流程",
+                "status": "pending",
+                "children": [
+                  {
+                    "id": "fc-acct-11",
+                    "type": "decision",
+                    "label": "重置邮件是否收到?",
+                    "yes_branch": {
+                      "id": "fc-acct-12",
+                      "type": "step",
+                      "label": "按邮件链接重置 + 回访"
+                    },
+                    "no_branch": {
+                      "id": "fc-acct-13",
+                      "type": "step",
+                      "label": "检查邮箱/反垃圾/电话二次验证"
+                    }
+                  }
+                ]
+              },
+              "no_branch": {
+                "id": "fc-acct-14",
+                "type": "step",
+                "label": "检查浏览器代理 + 缓存 + 尝试无痕模式",
+                "status": "pending",
+                "children": [
+                  {
+                    "id": "fc-acct-15",
+                    "type": "decision",
+                    "label": "换浏览器/无痕能打开?",
+                    "yes_branch": {
+                      "id": "fc-acct-16",
+                      "type": "step",
+                      "label": "指导员工清除原浏览器缓存"
+                    },
+                    "no_branch": {
+                      "id": "fc-acct-17",
+                      "type": "step",
+                      "label": "升级二线:检查 SSO 网关状态"
+                    }
+                  }
+                ]
+              }
+            }
+          ]
+        }
+      }
+    ]
+  }
+}