feat(keys): add API key group filter

[yang-nan-1]

📝 变更描述 / Description

在 /keys 页面新增按 API Key 分组的多选筛选。前端将所选分组作为重复的 group 查询参数发送；后端在列表和搜索接口中按这些分组过滤，并返回匹配总数。

AI-assisted: 本 PR 的冲突处理和验证由 AI 协助完成。

🚀 变更类型 / Type of change

• 🐛 Bug 修复 (Bug fix)
• ✨ 新功能 (New feature)
• ⚡ 性能优化 / 重构 (Refactor)
• 📝 文档更新 (Documentation)

🔗 关联任务 / Related Issue

• Closes # (无)

✅ 提交前检查项 / Checklist

• 人工确认: 我已亲自整理并撰写此描述，没有直接粘贴未经处理的 AI 输出。
• 非重复提交: 已检索现有 Issues 和 PR，未发现同一功能的开放项。
• Bug fix 说明: 不适用。
• 变更理解: 已确认前端查询参数、控制器和模型查询条件一致。
• 范围聚焦: 仅包含 API Key 分组筛选及必要的工具栏多选支持。
• 本地验证: go test ./controller -run 'Test(GetAllTokensFiltersByGroup|GetAllTokensFiltersByMultipleGroups|SearchTokensCombinesGroupAndNameSubstring|SearchTokensCombinesMultipleGroupsAndNameSubstring)' -count=1 通过。\n- [x] 安全合规: 未引入凭据。\n\n## 📸 运行证明 / Proof of Work\n后端分组筛选回归测试通过；合并分支已基于当前 main rebase 并解决 MAC 白名单代码与分组查询函数签名冲突。

[gitguardian]

⚠️ GitGuardian has uncovered 1 secret following the scan of your pull request.

Please consider investigating the findings and remediating the incidents. Failure to do so may lead to compromising the associated services or software components.

🔎 Detected hardcoded secret in your pull request

GitGuardian id	GitGuardian status	Secret	Commit	Filename
36243164	Triggered	Generic High Entropy Secret	c93318e	controller/token_test.go	View secret

🛠 Guidelines to remediate hardcoded secrets

1. Understand the implications of revoking this secret by investigating where it is used in your code.
2. Replace and store your secret safely. Learn here the best practices.
3. Revoke and rotate this secret.
4. If possible, rewrite git history. Rewriting git history is not a trivial act. You might completely break other contributing developers' workflow and you risk accidentally deleting legitimate data.

To avoid such incidents in the future consider

• following these best practices for managing and storing secrets including API keys and other credentials
• install secret detection on pre-commit to catch secret before it leaves your machine and ease remediation.

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