Add teaching Python agent CLI with Poetry and CI

tests/test_agent.py

@@ -0,0 +1,23 @@
+from agt.agent import Agent, Tool, echo_tool
+
+
+def test_agent_returns_default_message() -> None:
+    agent = Agent()
+    agent.register_tool(Tool("echo", "Echo input text", echo_tool))
+
+    result = agent.run("hello")
+
+    assert "教学用 Agent 骨架" in result
+    assert agent.messages[0].role == "user"
+    assert agent.messages[-1].role == "assistant"
+
+
+def test_load_skills_finds_skill_md(tmp_path) -> None:
+    skill_dir = tmp_path / "skills" / "writing"
+    skill_dir.mkdir(parents=True)
+    (skill_dir / "SKILL.md").write_text("# writing", encoding="utf-8")
+
+    agent = Agent()
+    skills = agent.load_skills(tmp_path / "skills")
+
+    assert skills == ["writing"]