Returns full Panchangam JSON for a date and city: Pancha Anga (Tithi, Nakshatra, Yoga, Karana), sky events (Sunrise, Sunset, Moonrise, Moonset), auspicious windows (Brahma Muhurta, Abhijit, Amrita Kalam), inauspicious windows (Rahu Kalam, Gulika, Yamagandam, Varjyam, Durmuhurtham), Choghadiya, special day flags, and field-group provenance states. New in 1.9.0: ghati_clock (sunrise-anchored ghati/vighati clock), nakshatra_pada (Moon's pada 1-4), vishaghati windows, bhadra_mukha/bhadra_puchha (Vishti split), sankramana_avoidance, in_panchaka_nakshatra, nakshatra_mukha (Adho/Urdhva/Tiryak), anandadi_yoga, is_khar_maasa/khar_maasa_name, is_pitru_paksha, simha_stha_guru/simha_stha_shukra (Drik only), guru_maudhya/shukra_maudhya (Drik only), disha_shoola_direction, panchaka_rahita. Args: date=YYYY-MM-DD, city=city name (or pass latitude+longitude for a custom location; timezone is derived if omitted), system=drik|surya_siddhanta|vakya (default: drik), ayanamsa=lahiri|raman|krishnamurti|true_chitrapaksha (default: lahiri; SS and Vakya accept the param for API symmetry but always use their own mean-motion model).