feat: cross-platform streaming polish output (Win/Linux/macOS)

[appergb]

User description

Summary

• 让润色 LLM 的 SSE chunk 边到达边逐字模拟键盘事件落到光标，用户感知到的处理时延显著降低（第一个 token 即开始落字）
• 三平台都覆盖：macOS（CGEvent + 临时切 ABC 输入源）、Windows（SendInput Unicode，绕过 TSF/IME）、Linux 实验（enigo + XTest）
• Opt-in（默认 false），不开等价于历史行为；条件不满足（Codex/Gemini provider / Raw / 翻译 / Secure Input 框）自动回落一次性插入

主要改动

• 新增 unicode_keystroke.rs，跨平台 Unicode 按键合成（macOS TIS 调度到主线程规避 macOS 14+ TSM 断言）
• polish.rs OpenAI-compatible provider 加 polish_streaming + 共用 SSE 解析（与 QA streaming 同款）
• coordinator.rs 加 StreamingPolishOutcome 三态 + polish_or_passthrough_streaming 分发器
• coordinator/dictation.rs::run_streaming_polish 主体：mpsc + spawn_blocking typer + 输入源恢复 + already_streamed 跳过 inserter
• UserPreferences 加 streaming_insert（默认 false）+ streaming_insert_save_clipboard（默认 true）
• 前端 Settings → Advanced 新增流式 Card（按平台分发 hint 文案），5 个 locale 完全对齐

Test plan

• cargo check --manifest-path src-tauri/Cargo.toml macOS host pass
• cargo test --lib 222 passed
• npm run build (tsc + vite) pass
• Windows-host CI 跑 cfg(target_os=windows) 分支 cargo check（依赖 release-tauri.yml）
• Linux-host CI 同上
• macOS 真机：中文系统输入法下流式正常，session 结束自动切回原输入源
• Windows 真机：流式 + 切到 Word / 浏览器 / 终端各跑一遍
• Linux Wayland 真机：失败回落到一次性插入

已知限制

• v1 仅 OpenAI-compatible provider 实装；Codex/Gemini 透明降级
• 密码框 / 1Password / SSH prompt 等 Secure Input 框拒绝合成按键 → 失败回落
• 流式路径下 apply_chinese_script_preference / apply_correction_rules v1 跳过（字已经流出去不好回退）

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PR Type

Enhancement, Bug fix

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Description

• Add opt-in streaming insertion pipeline

  • SSE deltas type directly to cursor

• Implement cross-platform Unicode keystrokes

  • macOS ABC, Windows SendInput, Linux enigo

• Preserve fallback on unsupported streaming

  • Raw path remains unchanged

• Add prefs, UI, translations

  • New toggles and localized labels

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Diagram Walkthrough

flowchart LR
  A["Settings toggle"] -- "enable streaming_insert" --> B["end_session dispatch"]
  B -- "eligible" --> C["run_streaming_polish"]
  C -- "SSE deltas" --> D["polish_streaming"]
  D -- "on_delta" --> E["unicode_keystroke"]
  C -- "fallback / success" --> F["one-shot insert or skip"]

Loading

File Walkthrough

	Relevant files
Enhancement	6 files coordinator.rs Dispatch streaming polish outcomes and fallbacks                  +99/-0    dictation.rs Stream deltas through keyboard typing                                        +300/-6  polish.rs Add streaming polish provider support                                        +217/-0  unicode_keystroke.rs Implement cross-platform Unicode typing helpers                    +413/-0  types.ts Extend user preferences TypeScript interface                          +7/-0      Settings.tsx Add streaming settings section to UI                                          +47/-0
Miscellaneous	1 files lib.rs Register Unicode keystroke helper module                                  +1/-0
Configuration changes	2 files types.rs Add streaming preference and clipboard fields                        +32/-0    ipc.ts Update mock settings for new fields                                            +2/-0
Documentation	5 files en.ts Add streaming settings English copy                                            +13/-0    ja.ts Add streaming settings Japanese copy                                          +13/-0    ko.ts Add streaming settings Korean copy                                              +13/-0    zh-CN.ts Add streaming settings Simplified Chinese copy                      +13/-0    zh-TW.ts Add streaming settings Traditional Chinese copy                    +13/-0
Tests	1 files stylePrefs.test.ts Extend preference fixtures for streaming                                  +2/-0

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[github-actions]

PR Reviewer Guide 🔍

(Review updated until commit ceda94e)

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 3 🔵🔵🔵⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Partial chunk loss typed_text is only updated after type_unicode_chunk(&delta) succeeds for the whole SSE delta. If the platform keystroke API fails after already emitting part of a multi-character delta, the successfully typed prefix is lost from typed_text. That makes the saved history/clipboard shorter than what the user actually saw, and if the failure happens on the first delta it can also fall back to one-shot insertion with characters already visible on screen, causing duplicates. let typer_handle = tokio::task::spawn_blocking(move || { let mut rx = rx; let mut typed_text = String::new(); let mut first_failure: Option<String> = None; while let Some(delta) = rx.blocking_recv() { if first_failure.is_some() { // 一旦类型链路出错（如 Secure Input 启用），后续 delta 全部丢弃，但仍 // 把 mpsc drain 完，避免发送端阻塞。 continue; } match crate::unicode_keystroke::type_unicode_chunk(&delta) { Ok(()) => { typed_text.push_str(&delta); } Err(e) => { log::error!( "[coord] streaming_insert: type_unicode_chunk failed at typed={} chars: {e}; \ dropping remaining deltas", typed_text.chars().count() ); first_failure = Some(e.to_string()); } } } (typed_text, first_failure)

[github-actions]

Persistent review updated to latest commit 822a0fb

[github-actions]

Persistent review updated to latest commit 4030380

[github-actions]

Persistent review updated to latest commit ceda94e