The Irish music trio Fódhla brings their high energy and stellar artistry to the stage at Arts Collaborative Medford. Fódhla sound is firmly rooted in the traditional Irish melodies and ornamentation that fiddler Ellery Klein, of Medford, and flute player Nicole Rabata honed during years spent abroad in Ireland’s cities Cork, Limerick and Ennis. Fiddle and flute tunes are superbly supported by guitarist Bethany Waickman, whose inventive, tasteful chords unfold with driving rhythm perfected from years of playing for contra…