Persist session state before break and update E2E test

Add update_session_state call before break in both while loops
when a composite returns a question directly, ensuring session
position is persisted to DB before exiting. Without this, the
next user reply could resolve against the wrong node/flow.

Update E2E test script to walk through composite sub-flows
(recommendation, jokes, spelling) and add Test 5 for the
stale collection → composite chaining path.

Author: hardbyte

app/services/chat_runtime.py

@@ -1381,6 +1381,15 @@ async def process_interaction(
                                     auto_result
                                 )
                                 chained_next_node = None
+                                # Persist session position before exiting loop
+                                session = await chat_repo.update_session_state(
+                                    db,
+                                    session_id=session.id,
+                                    state_updates={},
+                                    current_node_id=session_position,
+                                    current_flow_id=session_flow_id,
+                                    expected_revision=session.revision,
+                                )
                                 break
 
                             # Update position and continue
@@ -1582,6 +1591,15 @@ async def process_interaction(
                                     auto_result
                                 )
                                 chained_next = None
+                                # Persist session position before exiting loop
+                                session = await chat_repo.update_session_state(
+                                    db,
+                                    session_id=session.id,
+                                    state_updates={},
+                                    current_node_id=session_position,
+                                    current_flow_id=session_flow_id,
+                                    expected_revision=session.revision,
+                                )
                                 break
 
                             session_position = chained_next.node_id