feat: Add VolcEngine LLM provider support

- Add VolcEngine ProviderSpec entry in registry.py
- Add volcengine to ProvidersConfig class in schema.py
- Update model providers table in README.md
- Add description about VolcEngine coding plan endpoint

README.md

@@ -578,6 +578,7 @@ Config file: `~/.nanobot/config.json`
 > - **Groq** provides free voice transcription via Whisper. If configured, Telegram voice messages will be automatically transcribed.
 > - **Zhipu Coding Plan**: If you're on Zhipu's coding plan, set `"apiBase": "https://open.bigmodel.cn/api/coding/paas/v4"` in your zhipu provider config.
 > - **MiniMax (Mainland China)**: If your API key is from MiniMax's mainland China platform (minimaxi.com), set `"apiBase": "https://api.minimaxi.com/v1"` in your minimax provider config.
+> - **VolcEngine Coding Plan**: If you're on VolcEngine's coding plan, set `"apiBase": "https://ark.cn-beijing.volces.com/api/coding/v3"` in your volcengine provider config.
 
 | Provider | Purpose | Get API Key |
 |----------|---------|-------------|
@@ -591,6 +592,7 @@ Config file: `~/.nanobot/config.json`
 | `minimax` | LLM (MiniMax direct) | [platform.minimax.io](https://platform.minimax.io) |
 | `aihubmix` | LLM (API gateway, access to all models) | [aihubmix.com](https://aihubmix.com) |
 | `siliconflow` | LLM (SiliconFlow/硅基流动, API gateway) | [siliconflow.cn](https://siliconflow.cn) |
+| `volcengine` | LLM (VolcEngine/火山引擎) | [volcengine.com](https://www.volcengine.com) |
 | `dashscope` | LLM (Qwen) | [dashscope.console.aliyun.com](https://dashscope.console.aliyun.com) |
 | `moonshot` | LLM (Moonshot/Kimi) | [platform.moonshot.cn](https://platform.moonshot.cn) |
 | `zhipu` | LLM (Zhipu GLM) | [open.bigmodel.cn](https://open.bigmodel.cn) |

nanobot/config/schema.py

@@ -220,6 +220,7 @@ class ProvidersConfig(Base):
     minimax: ProviderConfig = Field(default_factory=ProviderConfig)
     aihubmix: ProviderConfig = Field(default_factory=ProviderConfig)  # AiHubMix API gateway
     siliconflow: ProviderConfig = Field(default_factory=ProviderConfig)  # SiliconFlow (硅基流动) API gateway
+    volcengine: ProviderConfig = Field(default_factory=ProviderConfig)  # VolcEngine (火山引擎) API gateway
     openai_codex: ProviderConfig = Field(default_factory=ProviderConfig)  # OpenAI Codex (OAuth)
     github_copilot: ProviderConfig = Field(default_factory=ProviderConfig)  # Github Copilot (OAuth)
 

nanobot/providers/registry.py

@@ -137,6 +137,24 @@ PROVIDERS: tuple[ProviderSpec, ...] = (
         model_overrides=(),
     ),
 
+    # VolcEngine (火山引擎): OpenAI-compatible gateway
+    ProviderSpec(
+        name="volcengine",
+        keywords=("volcengine", "volces", "ark"),
+        env_key="OPENAI_API_KEY",
+        display_name="VolcEngine",
+        litellm_prefix="openai",
+        skip_prefixes=(),
+        env_extras=(),
+        is_gateway=True,
+        is_local=False,
+        detect_by_key_prefix="",
+        detect_by_base_keyword="volces",
+        default_api_base="https://ark.cn-beijing.volces.com/api/v3",
+        strip_model_prefix=False,
+        model_overrides=(),
+    ),
+
     # === Standard providers (matched by model-name keywords) ===============
 
     # Anthropic: LiteLLM recognizes "claude-*" natively, no prefix needed.