fix(graph): handle cancel_node gracefully without raising exception#1524

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pgrayy wants to merge 3 commits intomainfrom

agent-tasks/1500

Commits on Jan 20, 2026

fix(graph): handle cancel_node gracefully without raising exception
strands-agent
committed
fix(graph): wrap cancel message in Exception to satisfy NodeResult type
strands-agent
committed
refactor(graph): simplify cancel_node to match Swarm pattern
strands-agent
committed