✨ feat: add Qwen ASR provider support

[nmvr2600]

Summary

添加阿里云 Qwen（通义千问）实时语音识别 Provider，支持使用 DashScope API 进行语音转文字。

Changes

Backend (Rust)

• koe-asr/src/qwen.rs: 新增 QwenAsrProvider 实现 WebSocket Realtime API
• koe-asr/src/lib.rs: 导出 QwenAsrProvider
• koe-asr/Cargo.toml: 添加 base64 依赖
• koe-core/src/lib.rs: 集成 Qwen provider 到 ASR 会话
• koe-core/src/config.rs: 新增 QwenAsrConfig 配置结构

Frontend (Objective-C)

• SPSetupWizardWindowController.m:
  • 新增 Qwen API Key 配置界面
  • 支持 Doubao/Qwen Provider 切换
  • 添加 ASR 连接测试功能

Configuration

• 新增 asr.qwen.api_key 配置项
• 新增 asr.qwen.language 配置项（默认 zh）

Testing

• ✅ 所有现有测试通过
• ✅ 新增 Qwen provider 基础测试
• ✅ 修复 2 个失败的 TranscriptAggregator 测试

Usage

在设置向导中选择 Qwen Provider 并填入 DashScope API Key 即可使用。

Related

• 阿里云 Qwen 实时语音识别文档：https://help.aliyun.com/zh/model-studio/qwen-real-time-speech-recognition

[missuo]

Review

Core functionality looks good

The Qwen ASR provider implementation, config integration, and UI changes for provider switching + test connection are solid.

Unnecessary changes

1. Formatting-only diffs — The following files have changes that are purely rustfmt reformatting, unrelated to the Qwen feature:

   • koe-core/src/llm/openai_compatible.rs — format! macro line wrapping
   • koe-core/src/prompt.rs — log::warn! and if statement reformatting
   • koe-core/src/session.rs — Session::new params and log::debug! reformatting
   • koe-core/src/dictionary.rs — log::info! reformatting
   • koe-asr/src/doubao.rs — .unwrap_or(false) line merge

   Please revert these — they add noise to the diff and make git blame harder to use.

2. NSLog removals — 4 NSLog statements removed in SPSetupWizardWindowController.m (config save, dictionary save, prompt save, "settings saved"). Unrelated to Qwen — should be a separate commit if intended.

3. Dead code in hotkey loading — triggerFound and cancelFound variables are assigned but never read. Remove them.

4. Hand-rolled base64 encoder — qwen.rs contains a ~40-line manual base64 implementation, but Cargo.toml already adds base64 = "0.22" as a dependency. Just use the crate.

5. .gitignore adding docs/ — Unrelated to this feature, should be a separate commit.

Suggestions

• AsrConfig pollution — The language field was added to the shared AsrConfig struct, but only Qwen uses it. Consider having each provider handle its own config internally, or at least document that this field is Qwen-specific.
• Duplicate error handling in test connection — testDoubaoConnection and testQwenConnection share a lot of identical error-matching logic. Consider extracting a common helper.

[missuo]

Re-review after feedback commit (3b407a9)

All previously flagged issues have been addressed:

• Formatting-only diffs reverted
• .gitignore and NSLog removals reverted
• Dead triggerFound/cancelFound variables removed
• Hand-rolled base64 replaced with the base64 crate

Remaining minor notes (non-blocking)

1. Hotkey loading refactor — The hotkey section in loadValuesForPane: still has cosmetic changes (splitting into triggerKeyRaw/cancelKeyRaw intermediate variables, adding blank lines and a comment). These are harmless but not strictly necessary for this PR.

2. AsrConfig as a shared struct — Qwen stuffs its api_key into the access_key field and leaves url, app_key, resource_id as empty strings. This works but is a bit of a code smell — the shared config struct is effectively Doubao-shaped and Qwen has to work around it. Fine for now, worth revisiting if a third provider is added.

3. ObjC test connection code duplication — testDoubaoConnection and testQwenConnection share ~80% identical error-handling logic. A shared helper like - (void)handleAsrTestError:(NSError *)error would reduce this.

LGTM — the core Qwen ASR implementation and UI integration look good. Approving.

[missuo]

BTW, please do not include any emojis in commit messages next time, and please follow the contribution requirements.

[missuo]

In addition, there should be no comments in Chinese. In principle, there should be no part of the test.