commands: add debugbundle command Lists ids contained in a bundle file. Useful for testing bundle-related commands.

wireproto: add known([id]) function known([Node]) -> [1/0] Returns 1/0 for each node, indicating whether it's known by the server. Needed for new discovery protocols introduced in later patches.

wireproto: fix decodelist to properly return empty list Needed by tests for next patch introducing known().