verbose live UI + tool-level SSE events + Groq default + regression tests

tests/test_llm.py

@@ -0,0 +1,15 @@
+"""Regression: LLM dispatcher exposes all three providers and rejects unknowns."""
+
+import pytest
+
+from api import llm
+
+
+def test_providers_registered():
+    assert set(llm._PROVIDERS) == {"groq", "anthropic", "openai"}
+
+
+def test_unknown_provider_raises(monkeypatch):
+    monkeypatch.setattr(llm.get_settings(), "llm_provider", "definitely-not-a-provider", raising=False)
+    with pytest.raises(ValueError, match="unknown llm_provider"):
+        llm.chat(system="s", user="u")