improve position tracking in the lexer (bug #57924) * oct-parse.yy (base_parser::bison_error): Fix error column adjustment. * lex.h, lex.ll (lexical_feedback::handle_language_extension_op, lexical_feedback::handle_assign_op, lexical_feedback::handle_language_extension_assign_op, lexical_feedback::handle_op_internal): Delete. Replace uses with calls to handle_op instead. (lexical_feedback::handle_op, lexical_feedback::handle_identifier, lexical_feedback::handle_superclass_identifier): Update token positions inside these functions. Remove updates from rules that use them. Consistently handle file position updates.