identify "x .foo@bar" or "x @foo" as command syntax (bug #55891) * lex.ll ({FQIDENT}{S}*@{S}*{FQIDENT}): If we are at the beginning of a statement and there is a space before the first "." or "@" character, parse as a normal identifier, which will lead to parsing as a command. Also set m_beginning_of_statement to false if a superclass identifier is found. * debug.cc: Use command syntax for dbstop commands with @ftp/dir and @audioplayer/set again as it provides a test for this form of command syntax.

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