Your hash isn't being built the way you think it is (hint: put a use Data::Dumper at the head of the code and then print Dumper %component_tree to see for yourself). You probably want something like this:

%component_tree = (
  component1 => {
    command1 => "001",
    command2 => "002",
  }
);
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etc. In which case you can get the command id for a command with e.g. $component_tree{component1}->{command1}