Add integration testing guide and prompts

- docs/workflow/INTEGRATION-TESTING.md - Full guide on integration testing
  - What it is vs unit/e2e tests
  - 5 principles to test per integration point
  - Folder structure suggestions
  - Self-improving loop for human findings
- integration-tests/ - Template for project's integration tests
  - README.md - What to test (Feynman fills per project)
  - package.json - Test runner setup
  - scripts/setup.sh - Service startup
  - scripts/teardown.sh - Cleanup
- docs/workflow/WORKFLOW.md - Added integration testing references
- docs/workflow/AGENT-PROMPTS.md - Added integration testing prompts
- docs/workflow/INDEX.md - Updated file structure

integration-tests/scripts/teardown.sh

@@ -0,0 +1,23 @@
+#!/bin/bash
+#
+# Teardown script for integration tests
+# Run this after tests to clean up services
+#
+# Edit this file to match your project's needs.
+#
+
+echo "=========================================="
+echo "Integration Tests Teardown"
+echo "=========================================="
+echo ""
+
+# TODO: Add commands to stop services
+# Example:
+#   echo "Stopping backend server..."
+#   pkill -f "node.*backend"
+#
+#   echo "Stopping database..."
+#   docker compose down
+
+echo "Teardown complete."
+echo ""