[Interfaces] Added ANBoolFieldValue.
[AN] Added support for boolean fields.
[Interfaces] Added terminal-related AN cats/types/fields.
[Util] Added AN::Field::TerminalActive field description.
[AN] Added support for terminal events.
[AN] Fixed crash on setting standard fields matchers.
[AN] Default rules for terminal events.
[ER] Keep whether the tab is current.
[ER] Emit a notification entity on terminal bell.