feat(providers): add APIFree support

Add APIFree as a built-in OpenAI-compatible provider. APIFree offers
agent-optimised models such as skywork-ai/skyclaw-v1 through an
OpenAI-compatible API at https://api.apifree.ai/agent/v1.

Changes:
- Register apifree provider in the provider registry
- Add config schema field
- Add documentation with configuration example
- Add provider tests, websocket channel tests, and webui tests
- Add provider icon in settings UI

tests/channels/test_websocket_channel.py

@@ -1034,6 +1034,8 @@ async def test_settings_api_returns_safe_subset_and_updates_whitelist(
         assert providers["skywork"]["default_api_base"] == "https://api.apifree.ai/v1"
         assert providers["ant_ling"]["label"] == "Ant Ling"
         assert providers["ant_ling"]["default_api_base"] == "https://api.ant-ling.com/v1"
+        assert providers["apifree"]["label"] == "APIFree"
+        assert providers["apifree"]["default_api_base"] == "https://api.apifree.ai/agent/v1"
         assert providers["atomic_chat"]["configured"] is False
         assert providers["atomic_chat"]["api_key_required"] is False
         assert providers["atomic_chat"]["default_api_base"] == "http://localhost:1337/v1"

tests/providers/test_apifree_provider.py

@@ -0,0 +1,71 @@
+"""Tests for the APIFree provider registration."""
+
+from unittest.mock import patch
+
+from nanobot.config.schema import Config, ProvidersConfig
+from nanobot.providers.openai_compat_provider import OpenAICompatProvider
+from nanobot.providers.registry import PROVIDERS, find_by_name
+
+
+def test_apifree_config_field_exists() -> None:
+    config = ProvidersConfig()
+    assert hasattr(config, "apifree")
+
+
+def test_apifree_provider_in_registry() -> None:
+    specs = {spec.name: spec for spec in PROVIDERS}
+    assert "apifree" in specs
+
+    apifree = specs["apifree"]
+    assert apifree.backend == "openai_compat"
+    assert apifree.env_key == "APIFREE_API_KEY"
+    assert apifree.display_name == "APIFree"
+    assert apifree.default_api_base == "https://api.apifree.ai/agent/v1"
+
+
+def test_find_by_name_accepts_apifree_spellings() -> None:
+    spec = find_by_name("apifree")
+    assert spec is not None
+
+
+def test_apifree_model_auto_matches_with_default_api_base() -> None:
+    config = Config.model_validate(
+        {
+            "providers": {
+                "apifree": {
+                    "apiKey": "apifree-key",
+                },
+            },
+            "agents": {
+                "defaults": {
+                    "model": "skywork-ai/skyclaw-v1",
+                },
+            },
+        }
+    )
+
+    assert config.get_provider_name("skywork-ai/skyclaw-v1") == "apifree"
+    assert config.get_api_key("skywork-ai/skyclaw-v1") == "apifree-key"
+    assert config.get_api_base("skywork-ai/skyclaw-v1") == "https://api.apifree.ai/agent/v1"
+
+
+def test_apifree_preserves_official_model_name() -> None:
+    spec = find_by_name("apifree")
+    with patch("nanobot.providers.openai_compat_provider.AsyncOpenAI"):
+        provider = OpenAICompatProvider(
+            api_key="apifree-key",
+            default_model="skywork-ai/skyclaw-v1",
+            spec=spec,
+        )
+
+    kwargs = provider._build_kwargs(
+        messages=[{"role": "user", "content": "hi"}],
+        tools=None,
+        model="skywork-ai/skyclaw-v1",
+        max_tokens=1024,
+        temperature=0.7,
+        reasoning_effort=None,
+        tool_choice=None,
+    )
+
+    assert kwargs["model"] == "skywork-ai/skyclaw-v1"