chore: import upstream snapshot with attribution

examples/canvas/langgraph-python/scripts/setup-agent.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+# Navigate to the agent directory
+cd "$(dirname "$0")/../agent" || exit 1
+
+# Create virtual environment if it doesn't exist
+if [ ! -d ".venv" ]; then
+  python3 -m venv .venv || python -m venv .venv
+fi
+
+# Activate the virtual environment
+source .venv/bin/activate
+
+# Install requirements using pip3 or pip
+(pip3 install -r requirements.txt || pip install -r requirements.txt)