Add Session multi-party call support and show history

- Add CallRecord dataclass for tracking call history
- Extend Session with call_history, active_real_caller, ai_respond_mode, auto_followup
- Add get_show_history() for AI caller context about earlier calls
- Update get_conversation_summary() to handle host/real_caller/ai_caller roles
- Update reset() to clear new fields
- Add tests for all new functionality

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/test_session.py

@@ -0,0 +1,89 @@
+import sys
+sys.path.insert(0, "/Users/lukemacneil/ai-podcast")
+
+from backend.main import Session, CallRecord
+
+
+def test_call_record_creation():
+    record = CallRecord(
+        caller_type="real",
+        caller_name="Dave",
+        summary="Called about his wife leaving",
+        transcript=[{"role": "host", "content": "What happened?"}],
+    )
+    assert record.caller_type == "real"
+    assert record.caller_name == "Dave"
+
+
+def test_session_call_history():
+    s = Session()
+    assert s.call_history == []
+    record = CallRecord(
+        caller_type="ai", caller_name="Tony",
+        summary="Talked about gambling", transcript=[],
+    )
+    s.call_history.append(record)
+    assert len(s.call_history) == 1
+
+
+def test_session_active_real_caller():
+    s = Session()
+    assert s.active_real_caller is None
+    s.active_real_caller = {
+        "call_sid": "CA123", "phone": "+15125550142",
+        "channel": 3, "name": "Caller #1",
+    }
+    assert s.active_real_caller["channel"] == 3
+
+
+def test_session_three_party_conversation():
+    s = Session()
+    s.start_call("1")  # AI caller Tony
+    s.add_message("host", "Hey Tony")
+    s.add_message("ai_caller:Tony", "What's up man")
+    s.add_message("real_caller:Dave", "Yeah I agree with Tony")
+    assert len(s.conversation) == 3
+    assert s.conversation[2]["role"] == "real_caller:Dave"
+
+
+def test_session_get_show_history_summary():
+    s = Session()
+    s.call_history.append(CallRecord(
+        caller_type="real", caller_name="Dave",
+        summary="Called about his wife leaving after 12 years",
+        transcript=[],
+    ))
+    s.call_history.append(CallRecord(
+        caller_type="ai", caller_name="Jasmine",
+        summary="Talked about her boss hitting on her",
+        transcript=[],
+    ))
+    summary = s.get_show_history()
+    assert "Dave" in summary
+    assert "Jasmine" in summary
+    assert "EARLIER IN THE SHOW" in summary
+
+
+def test_session_reset_clears_history():
+    s = Session()
+    s.call_history.append(CallRecord(
+        caller_type="real", caller_name="Dave",
+        summary="test", transcript=[],
+    ))
+    s.active_real_caller = {"call_sid": "CA123"}
+    s.ai_respond_mode = "auto"
+    s.reset()
+    assert s.call_history == []
+    assert s.active_real_caller is None
+    assert s.ai_respond_mode == "manual"
+
+
+def test_session_conversation_summary_three_party():
+    s = Session()
+    s.start_call("1")
+    s.add_message("host", "Tell me what happened")
+    s.add_message("real_caller:Dave", "She just left man")
+    s.add_message("ai_caller:Tony", "Same thing happened to me")
+    summary = s.get_conversation_summary()
+    assert "Dave" in summary
+    assert "Tony" in summary