feat(responses): 实现响应状态续接路由

[tbphp]

关联 Issue / Related Issue

无关联 Issue。

变更内容 / Change Content

• Bug 修复 / Bug fix
• 新功能 / New feature
• 其他改动 / Other changes

HTTP/SSE Responses 的后续请求原先可能被调度到无法访问上一轮响应的凭据。本次按 AccessKeyID + response_id 记录归属，续接仅使用当前路由仍允许的原凭据；例如首轮由 A 生成响应，即使下一次普通轮询应选 B，续接也只能使用 A。

• ID 路由与提示词软亲和互斥，不受亲和开关影响；实际命中时复用现有亲和图标。继续使用原候选过滤、健康裁决、共享记账和受限认证刷新重试，普通失败不会换凭据。
• 响应 ID 在 JSON/SSE 下发前写入有界内存索引，复用正常停机 checkpoint 恢复。请求路径不增加 DB 或文件 IO，不新增依赖、数据表或迁移。
• 管理面保存与匹配规则应用时保护 previous_response_id。旧覆盖配置仍可加载和查看；应用时允许旧规则删除不存在的字段，仍拒绝删除实际存在的字段（包括 null 和空字符串）或通过 set 注入该字段。
• 同步更新中文、英文、日文 README。

兼容性与边界：

• 按原生 Responses Create 和现有 upstream_managed 存储声明自动接入，当前包括 openai、gpt_load、xai、newapi、cliproxyapi、sub2api，不新增渠道开关。中转渠道仅保证回到原下一跳，实际状态可用性由上游决定。无状态、转换以及明确 store:false 的响应不登记新 ID；Codex 订阅的 WebSocket 接入留在后续阶段。
• 纯 ID 续接不再要求查询、删除、取消等完整生命周期能力，调度与执行器使用同一存储要求。与 conversation、background、保存的 prompt 或其他资源引用混用时继续保留原条件，其他 Responses 资源操作的归属路由不在本次范围。
• 未知、过期或淘汰的 ID 本地拒绝，包括升级前和网关外创建的 ID；非字符串、非 null 值及重复字段返回本地 400。
• 绑定默认保留 30 天，最多 100,000 条、单个 ID 最大 4 KiB、ID 文本合计 16 MiB。超长 ID 拒绝登记和下发，快照恢复时跳过。仅承诺正常停机成功保存 checkpoint 后恢复，不保证崩溃恢复或上游历史持续有效。

验证：make check 通过。Go 回归覆盖多凭据续接、AccessKey 隔离、亲和互斥、SSE 登记时点、冷却恢复、身份变更、失败不换号、参数覆盖、索引边界和 checkpoint 恢复。六个渠道均通过实际 Bifrost 执行链路连接本地 HTTP 上游，验证连续请求保留原凭据和 previous_response_id，store:false 仍可使用已有绑定且不登记新 ID；混合资源、无状态和转换候选继续受限。这些验证不代表真实上游账号的状态存储保证。未运行本地 race 或前端测试。

自查清单 / Checklist

• 我已运行 make check，或在说明中写明无法运行的原因和未验证范围。 / I ran make check, or documented why it could not run and what remains unverified.
• 本 PR 范围聚焦，未包含无关改动。 / This PR is focused and contains no unrelated changes.
• 我已更新必要的公开文档或发布说明。 / I updated any required public documentation or release notes.
• 我已确认提交、日志和测试数据不包含敏感信息。 / I confirmed that commits, logs, and fixtures contain no sensitive data.
• 如适用，我已说明兼容性或数据迁移影响。 / Where applicable, I documented compatibility or data-migration impact.

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-09T15:13:03.761776Z	73ee9b6	New commits

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[coderabbitai]

📝 Walkthrough

Walkthrough

本次变更为 OpenAI Responses 增加 previous_response_id 续接支持。系统按 AccessKey 记录响应归属，并在后续请求中固定允许的凭据。响应归属支持 TTL、容量限制、LRU 淘汰和运行时检查点恢复。参数覆盖不能修改 previous_response_id。README 文档同步说明支持范围和限制。

Priority: ➖ Normal

Merge Risk: 🟡 Moderate · up to 73ee9

Empty continuation IDs may bypass local validation, and the documentation advertises continuation channels beyond the stated support scope. Resolve these contract mismatches before merge.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 3.64% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 55 functions across 35 files. (3 skipped: …	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	标题“feat(responses): 实现响应状态续接路由”准确概括了本次 PR 的主要变更，内容明确且简洁。
Description check	✅ Passed	描述已说明新功能、实现范围、兼容性边界、验证结果和自查清单。描述明确记录了未运行 race 测试和前端测试的范围；“无关联 Issue”也已明确说明。

Full details: Docstring Coverage

Explanation

Docstring coverage is 3.64% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 55 functions across 35 files. (3 skipped: 3 unsupported.)

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[coderabbitai]

Actionable comments posted: 1

Note

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🟡 Other comments (1)

internal/dialect/request_fields.go-79-80 (1)

79-80: 🎯 Functional Correctness | 🟡 Minor | ⚡ Quick win

拒绝空的 previous_response_id。

当客户端发送 {"previous_response_id":""} 时，Decode 会成功，但 PreviousResponseID 保持为空。后续代码将空值视为非续接请求，因此跳过响应归属查找并把无效字段转发到上游，而不是在本地拒绝格式非法的 ID。

请在保留 null 支持的同时拒绝空字符串，并增加该用例的测试。

建议修改

-			if err := decoder.Decode(&result.PreviousResponseID); err != nil {
+			var previousResponseID *string
+			if err := decoder.Decode(&previousResponseID); err != nil {
 				return RequestMetadata{}, fmt.Errorf("previous_response_id must be a string or null")
 			}
+			if previousResponseID != nil {
+				if *previousResponseID == "" {
+					return RequestMetadata{}, fmt.Errorf("previous_response_id must be non-empty")
+				}
+				result.PreviousResponseID = *previousResponseID
+			}

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Configuration used: Organization UI

Review profile: QUIET

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Run ID: 2b7fcce6-71a6-4baa-b60e-91de4b1d9f6f

📥 Commits

Reviewing files that changed from the base of the PR and between d417b7d and 69cb135.

📒 Files selected for processing (30)

• README.md
• README_CN.md
• README_JP.md
• internal/app/runtime_checkpoint.go
• internal/app/runtime_checkpoint_test.go
• internal/app/scheduling_checkpoint_test.go
• internal/container/container.go
• internal/control/group_create.go
• internal/control/group_settings_test.go
• internal/dialect/anthropic.go
• internal/dialect/dialect.go
• internal/dialect/openai.go
• internal/dialect/openai_embeddings.go
• internal/dialect/openai_images.go
• internal/dialect/openai_responses.go
• internal/dialect/openai_responses_test.go
• internal/dialect/request_fields.go
• internal/dialect/request_fields_test.go
• internal/dialect/rerank.go
• internal/gateway/execution_forward.go
• internal/gateway/forward.go
• internal/gateway/handler.go
• internal/gateway/reason.go
• internal/gateway/reason_test.go
• internal/gateway/responses_continuation.go
• internal/gateway/responses_continuation_test.go
• internal/parameteroverride/response_continuation_test.go
• internal/parameteroverride/rules.go
• internal/state/response_bindings.go
• internal/state/response_bindings_test.go

Included review availability: Your plan provides up to 8 included reviews per hour; 7 remain after this review.

[coderabbitai]

Actionable comments posted: 1

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ℹ️ Review info

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Configuration used: Organization UI

Review profile: QUIET

Plan: Advanced

Run ID: c6d4b18d-faa4-4862-855e-bf7eb0d01e79

📥 Commits

Reviewing files that changed from the base of the PR and between 7f28bbd and a9bc90f.

📒 Files selected for processing (16)

• README.md
• README_CN.md
• README_JP.md
• internal/dialect/request_execution.go
• internal/dialect/request_execution_test.go
• internal/execution/bifrost/executor.go
• internal/execution/contracts.go
• internal/execution/contracts_test.go
• internal/execution/validation.go
• internal/gateway/execution_forward.go
• internal/gateway/forward.go
• internal/gateway/handler.go
• internal/gateway/responses_continuation.go
• internal/gateway/responses_continuation_test.go
• internal/scheduler/channel_scheduler_test.go
• internal/scheduler/inspect.go

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[tbphp]

针对审查汇总中剩余两项建议，保持现有实现：

• 空 previous_response_id：当前契约将缺省、null 和空字符串视为未提供续接 ID；非字符串、非 null 值以及重复字段仍在本地拒绝。相关回归测试 已通过，保留这一兼容行为。
• 注释覆盖率 80%：该阈值不是仓库质量门禁。当前提交 a9bc90fa 的 make check 已通过，不为该阈值批量添加注释。