more explicit default_port;

tuned messages;

tuned;

proper initialization of settings: avoid accidental intrusion from parent process environment;

clarified solr_data directory, provided via settings;

explicit settings FIND_FACTS_WEB and option -w, outside of source (immutable) directory;

tuned message;

implicit session build, similar to "isabelle export";

tuned message;

proper Console_Progress as for other command-line tools;

tuned messages: more formal;

clarified signature: progress is usually optional;