Can I carry raw/hard (not the liquid one) honey in hand luggage when travelling from Lithuania (Vilna) to Stockholm with Airbaltics?
Maybe. It depends on airport (I don't know Vilna) and on security staff. Often they allow it, but it is officially forbidden. See e.g. https://www.gov.uk/hand-luggage-restrictions:
Liquids include: (...) liquid or semi-liquid foods, for example soup, jam, honey and syrups
It might depend on the daily mood of whoever is screening your hand luggage, but honey can be considered a paste and therefore prohibited in hand luggage.