draft resume method
fix docblocks and typos
add docblocks, correct some typehinting to interfaces, and simplify logic on accept() method
adding some docblocks and @inheritdoc annotations, missing typehint and improving comments
simplify workflow accept() method
rename resume to flow and add optional token
add bolean result into flow() method
introduce resume() on nodes
plugging first default test scenario wip
add logger test handler on tests so that output log does not go to stdout
troubleshooting failure resume on a non object