feature: X-Talk Rust 迁移翻译版（Phase 0–2）

[RickyQzh]

Summary

在 fork 上落地分层 Rust 运行时 xtalk-rs（Phase 0–2），与现有 Python X-Talk 并存：

• 设计与计划：docs/superpowers/specs/2026-08-08-rust-port-design.md、docs/superpowers/plans/2026-08-08-rust-port-implementation.md
• rust/ workspace：xtalk-events / bus / models / pipeline / protocol / serving / server
• Dummy ASR/TTS/VAD/Agent 全路径 + 打断；axum dummy_server；线协议兼容现有前端
• Phase 2：HttpChatAgent（openai_compat + ${ENV}）；SSE delta 已 coalesce 为单段回复
• CI：.github/workflows/rust-check.yml；教程：docs/tutorial/rust_runtime.md / .zh.md

Test plan

• cd rust && cargo fmt --all -- --check
• cargo clippy --workspace --all-targets -- -D warnings
• cargo test --workspace（52 passed）
• WS smoke：session_attached / ping→pong / 合成 VAD→ASR→resp→TTS
• 真人麦克风联调 sample 前端（需处理 auth stub）
• config.openai.json + 真实 OPENAI_API_KEY 端到端

Notes

• Phase 3 native/FFI 不在本 PR
• 无 captioner/recording/persistence；auth 默认 Disabled（文档已说明）

  

[Copilot]

Pull request overview

This PR introduces an initial Rust runtime (“xtalk-rs”, Phase 0–2) alongside the existing Python backend, including an event-driven session model (EventBus/Managers/Pipeline), an axum WebSocket server compatible with the current frontend wire protocol, and docs/CI to support development and testing.

Changes:

• Add a new rust/ Cargo workspace implementing core runtime crates (xtalk-events, xtalk-bus, xtalk-models, xtalk-pipeline, xtalk-protocol, xtalk-serving, xtalk-server) plus a runnable dummy_server example.
• Implement end-to-end dummy ASR→Agent→TTS flow with barge-in/interrupt handling and protocol canary tests for frontend compatibility.
• Add HttpChatAgent for OpenAI-compatible SSE streaming, plus CI workflow and bilingual tutorial docs.

Reviewed changes

Copilot reviewed 68 out of 68 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
rust/rust-toolchain.toml	Pins Rust toolchain + components for formatting/linting consistency.
rust/Cargo.toml	Defines the Rust workspace members and shared dependency pins.
rust/.gitignore	Rust workspace ignore rules (build outputs / backups / lockfile).
rust/examples/dummy_server/Cargo.toml	Adds a runnable example binary crate for the Rust server stack.
rust/examples/dummy_server/src/main.rs	Example entrypoint loading config and starting xtalk_server.
rust/examples/dummy_server/config.dummy.json	Dummy pipeline server config for local smoke testing.
rust/examples/dummy_server/config.openai.json	Example config wiring openai_compat agent via env key expansion.
rust/crates/xtalk-events/Cargo.toml	Declares xtalk-events crate dependencies.
rust/crates/xtalk-events/src/lib.rs	Defines core event types (Event, EventMeta) and helpers.
rust/crates/xtalk-events/tests/event_type_tests.rs	Canary tests for event type-name parity and extension events.
rust/crates/xtalk-bus/Cargo.toml	Declares xtalk-bus crate dependencies.
rust/crates/xtalk-bus/src/lib.rs	Implements async priority EventBus with error recursion/rate controls.
rust/crates/xtalk-bus/tests/bus_tests.rs	Tests handler ordering, resilience, and error cooldown behavior.
rust/crates/xtalk-models/Cargo.toml	Declares model-trait crate dependencies (reqwest, tokio, etc.).
rust/crates/xtalk-models/src/lib.rs	Re-exports model traits + dummy/http implementations.
rust/crates/xtalk-models/src/error.rs	Defines ModelError used across model traits.
rust/crates/xtalk-models/src/asr.rs	ASR trait + dummy ASR implementation.
rust/crates/xtalk-models/src/tts.rs	TTS trait + dummy TTS implementation producing raw PCM chunks.
rust/crates/xtalk-models/src/vad.rs	VAD trait + dummy VAD implementation.
rust/crates/xtalk-models/src/agent.rs	Agent trait + dummy agent and AgentContext.
rust/crates/xtalk-models/src/http_agent.rs	Implements OpenAI-compatible HTTP/SSE chat agent with cancellation.
rust/crates/xtalk-models/tests/dummy_tests.rs	Tests dummy model behavior and basic invariants.
rust/crates/xtalk-models/tests/http_agent_tests.rs	Tests SSE streaming coalescing and cancellation behavior.
rust/crates/xtalk-pipeline/Cargo.toml	Declares pipeline crate deps.
rust/crates/xtalk-pipeline/src/lib.rs	Pipeline trait + DefaultPipeline and per-session clone behavior.
rust/crates/xtalk-pipeline/tests/pipeline_tests.rs	Tests session cloning isolates state between sessions.
rust/crates/xtalk-protocol/Cargo.toml	Declares protocol crate deps.
rust/crates/xtalk-protocol/src/lib.rs	Exposes inbound parsing, outbound encoding, and protocol types.
rust/crates/xtalk-protocol/src/inbound.rs	Parses inbound JSON control frames into InboundMessage.
rust/crates/xtalk-protocol/src/outbound.rs	Encodes outbound {"action","data"} messages and constants.
rust/crates/xtalk-protocol/src/fixtures/vad_speech_start.json	Inbound fixture for protocol canary tests.
rust/crates/xtalk-protocol/src/fixtures/ping.json	Inbound fixture for protocol canary tests.
rust/crates/xtalk-protocol/src/fixtures/session_config.json	Inbound fixture for protocol canary tests.
rust/crates/xtalk-protocol/tests/protocol_tests.rs	Tests protocol parsing/encoding expectations and unknown action behavior.
rust/crates/xtalk-serving/Cargo.toml	Declares serving-layer crate deps and internal crate links.
rust/crates/xtalk-serving/src/lib.rs	Public re-exports for the serving layer API surface.
rust/crates/xtalk-serving/src/manager.rs	Defines the Manager trait for bus-registered components.
rust/crates/xtalk-serving/src/service.rs	Implements per-session Service with bus + pipeline + managers.
rust/crates/xtalk-serving/src/service_manager.rs	Tracks active sessions and integrates session limiting and factories.
rust/crates/xtalk-serving/src/session_limiter.rs	Implements a simple concurrent session slot limiter.
rust/crates/xtalk-serving/src/modules/mod.rs	Modules wiring + WsSink abstraction for outbound frames.
rust/crates/xtalk-serving/src/modules/input_gateway.rs	Maps inbound WS frames to bus events and ping→pong handling.
rust/crates/xtalk-serving/src/modules/output_gateway.rs	Maps bus events to outbound WS frames (JSON + binary).
rust/crates/xtalk-serving/src/modules/vad_manager.rs	Optional server-side VAD edge-detection emitting speech start/end.
rust/crates/xtalk-serving/src/modules/asr_manager.rs	Preroll-buffered ASR manager driven by VAD/turn events.
rust/crates/xtalk-serving/src/modules/llm_agent_context_manager.rs	Bridges ASR final events into LLM consume requests.
rust/crates/xtalk-serving/src/modules/llm_agent_generation_manager.rs	Runs agent acceptance, emits ResponseUpdate/Finish, supports cancellation.
rust/crates/xtalk-serving/src/modules/tts_manager.rs	Runs TTS synthesis in a worker loop; supports stop/cancel and FIFO text queue.
rust/crates/xtalk-serving/src/modules/turn_taking_manager.rs	Implements barge-in logic: stop TTS/LLM when client starts speaking mid-TTS.
rust/crates/xtalk-serving/tests/service_lifecycle_tests.rs	Tests manager registration and bus shutdown semantics.
rust/crates/xtalk-serving/tests/session_limiter_tests.rs	Tests slot acquisition/release and ServiceManager connect/disconnect behavior.
rust/crates/xtalk-serving/tests/gateway_tests.rs	Tests Input/Output gateway mappings and WS sink forwarding.
rust/crates/xtalk-serving/tests/asr_manager_tests.rs	Tests ASR manager behavior across speech start/end and turn events.
rust/crates/xtalk-serving/tests/pipeline_flow_tests.rs	Integration tests for event ordering, FIFO TTS, and error terminal behavior.
rust/crates/xtalk-serving/tests/interrupt_tests.rs	Tests barge-in interruption and post-stop enqueue preservation.
rust/crates/xtalk-serving/tests/frontend_compat_tests.rs	Wire-protocol canaries for outbound JSON keys expected by the frontend.
rust/crates/xtalk-server/Cargo.toml	Adds axum server crate wiring and binary configuration.
rust/crates/xtalk-server/src/lib.rs	Re-exports server building blocks (build_app, serve, config/auth types).
rust/crates/xtalk-server/src/main.rs	Server binary entrypoint loading config and starting the axum app.
rust/crates/xtalk-server/src/config.rs	Loads JSON config, expands ${ENV}, and builds pipelines/models.
rust/crates/xtalk-server/src/auth.rs	Phase-1 allow-all auth mode + token extraction hook for later enforcement.
rust/crates/xtalk-server/src/app.rs	Builds axum router and WS session loop backed by ServiceManager/Managers.
rust/crates/xtalk-server/tests/ws_smoke.rs	WS integration smoke test for session_attached and ping→pong.
docs/tutorial/rust_runtime.md	English tutorial for running the Rust runtime and pointing frontend WS to it.
docs/tutorial/rust_runtime.zh.md	Chinese tutorial counterpart for the Rust runtime setup and notes.
docs/superpowers/specs/2026-08-08-rust-port-design.md	Rust port design spec (Phase 0–2 scope/architecture).
docs/superpowers/plans/2026-08-08-rust-port-implementation.md	Implementation plan/checklist for Phase 0–2 deliverables.
.github/workflows/rust-check.yml	Adds Rust CI workflow (fmt/clippy/tests + OpenSSL deps for reqwest).

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.