GitLab

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent

)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

Claude Code v2.1.78 起将 metadata.user_id 从拼接字符串改为 JSON：
旧: user_{hex}_account_{uuid}_session_{uuid}
新: {"device_id":"...","account_uuid":"...","session_id":"..."}

新增集中解析/格式化模块 metadata_userid.go：
- ParseMetadataUserID: 自动识别两种格式，提取 DeviceID/AccountUUID/SessionID
- FormatMetadataUserID: 根据 UA 版本输出对应格式（>= 2.1.78 输出 JSON）
- ExtractCLIVersion: 从 UA 提取版本号，消除与 ClaudeCodeValidator.ExtractVersion 的重复

修改消费者统一使用新模块：
- claude_code_validator: 用 ParseMetadataUserID 替代只匹配旧格式的 userIDPattern
- identity_service: RewriteUserID/WithMasking 增加 fingerprintUA 参数，
  解析用 ParseMetadataUserID，输出用 FormatMetadataUserID（版本感知）
- gateway_service: GenerateSessionHash 用 ParseMetadataUserID 提取 session_id，
  buildOAuthMetadataUserID 用 FormatMetadataUserID 输出版本匹配格式，
  两处 RewriteUserIDWithMasking 调用传入 fp.UserAgent
- account_test_service: generateSessionString 改用 FormatMetadataUserID，
  自动跟随 DefaultHeaders UA 版本

删除三个旧正则: userIDPattern, userIDRegex, sessionIDRegex
统一 hex 匹配为 [a-fA-F0-9]，修复旧 userIDRegex 只匹配小写的不一致

ParseGatewayRequest only parsed Anthropic format (system/messages),
ignoring Gemini native format (systemInstruction/contents). This caused
GenerateSessionHash to produce identical hashes for all Gemini sessions.

Add protocol parameter to ParseGatewayRequest to branch between
Anthropic and Gemini parsing. Update GenerateSessionHash message
traversal to extract text from both formats.

Mix SessionContext (ClientIP, UserAgent, APIKeyID) into
GenerateSessionHash 3rd-level fallback to differentiate requests
from different users sending identical content.

Also switch hashContent from SHA256-truncated to XXHash64 for
better performance, and optimize Trie Lua script to match from
longest prefix first.