feat: 支持配置运维健康评分阈值

[Clarence12138]

变更说明

• 为 ops_metric_thresholds 增加业务健康评分专用阈值：错误率满分/零分点、TTFT P99 满分/零分点
• 后端健康分计算改为读取配置，默认值保持现有硬编码行为不变
• 前端两个运维阈值设置入口补齐新增字段、默认值和校验文案
• 旧配置缺失新增字段时会自动补默认值，避免升级后健康分突变

验证

• ./node_modules/.bin/vue-tsc --noEmit
• ./node_modules/.bin/vitest run src/views/admin/ops src/components/admin/monitor src/components/common/__tests__ --passWithNoTests

说明：当前本地环境没有可用的 go/gofmt 工具链，后端单测未能在本机执行；已补充对应 unit test 用例。

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[Clarence12138]

I have read the CLA Document and I hereby sign the CLA sonnet ***@***.*** 原始邮件 发件人：github-actions[bot] ***@***.***> 发件时间：2026年5月5日 17:26 收件人：Wei-Shaw/sub2api ***@***.***> 抄送：Jiaxiang Zhang ***@***.***>, Author ***@***.***> 主题：Re: [Wei-Shaw/sub2api] feat: 支持配置运维健康评分阈值 (PR #2201) github-actions[bot] left a comment (Wei-Shaw/sub2api#2201) Thank you for your contribution! Before we can merge this PR, we need you to sign our Contributor License Agreement (CLA). To sign, please reply with the following comment: I have read the CLA Document and I hereby sign the CLA You only need to sign once — it will be valid for all your future contributions to this project. I have read the CLA Document and I hereby sign the CLA You can retrigger this bot by commenting recheck in this Pull Request. Posted by the CLA Assistant Lite bot. — Reply to this email directly, view it on GitHub, or unsubscribe. Triage notifications on the go with GitHub Mobile for iOS or Android. You are receiving this because you authored the thread.

[Clarence12138]

I have read the CLA Document and I hereby sign the CLA