chore: import upstream snapshot with attribution

showcase/integrations/ms-agent-python/qa/hitl-in-chat.md

@@ -0,0 +1,57 @@
+# QA: Human in the Loop — MS Agent Framework (Python)
+
+## Prerequisites
+
+- Demo is deployed and accessible
+- Agent backend is healthy (check /api/health)
+
+## Test Steps
+
+### 1. Basic Functionality
+
+- [ ] Navigate to the HITL demo page (`/demos/hitl`) > _Note: the URL path `/demos/hitl` is intentionally shorter than the feature id `hitl-in-chat`._
+- [ ] Verify the chat interface loads in a centered max-w-4xl container
+- [ ] Verify the chat input placeholder "Type a message" is visible
+- [ ] Send a basic message
+- [ ] Verify the agent responds
+
+### 2. Feature-Specific Checks
+
+#### Suggestions
+
+- [ ] Verify "Simple plan" suggestion button is visible
+- [ ] Verify "Complex plan" suggestion button is visible
+- [ ] Click the "Simple plan" suggestion
+- [ ] Verify it triggers a message about planning a trip to Mars in 5 steps
+
+#### Step Selection and Approval
+
+The HITL demo renders a single StepSelector card regardless of whether
+the underlying flow uses an interrupt hook or a frontend HITL tool. The
+framework-specific hook name is an implementation detail covered in each
+package's demo source; QA below validates the user-visible card behavior.
+
+- [ ] Send "Plan a trip to Mars in 5 steps"
+- [ ] Verify the StepSelector card appears (`data-testid="select-steps"`)
+- [ ] Verify step items are displayed with checkboxes (`data-testid="step-item"`)
+- [ ] Verify step text is visible (`data-testid="step-text"`)
+- [ ] Verify the selected count display shows "N/N selected"
+- [ ] Toggle a step checkbox off and verify the count decreases
+- [ ] Toggle it back on and verify the count increases
+- [ ] Click "Perform Steps (N)" / "Confirm (N)" button
+- [ ] Verify the agent continues processing after confirmation
+- [ ] In a new conversation, trigger the same flow and click "Reject" (where present)
+- [ ] Verify the card reflects the decision (Accepted / Rejected) and buttons disable
+
+### 3. Error Handling
+
+- [ ] Send an empty message (should be handled gracefully)
+- [ ] Verify no console errors during normal usage
+
+## Expected Results
+
+- Chat loads within 3 seconds
+- Agent responds within 10 seconds
+- Step selector renders with toggleable checkboxes
+- Accept/Reject flow completes without errors
+- No UI errors or broken layouts