Swiss Ephemeris REST API — Python/FastAPI Astrology Backend

We need a Python/FastAPI REST API that calculates accurate natal astrology charts using Swiss Ephemeris (pyswisseph). The API must support 13 celestial bodies, 10 house systems, aspects, transits, progressions, and synastry. Results must match professional ephemeris to sub-arcminute accuracy. Cities database (GeoNames cities500) for birth location lookup. Deployable via Docker. Detailed project brief document provided.