astroinsightapi/astroinsight-ruby-sdk ? reverse-engineered prompt

Build me a clean Ruby gem for the Astro Insight API, using pure Ruby with no extra dependencies.

I want a simple client that handles authentication with a client id and client secret, lets me set things like language and ayanamsha, and gives me easy access to the main astrology features from the README, like Vedic astrology, matchmaking, Panchang, Muhurta, tarot, horoscope, numerology, Chinese astrology, and geo lookup.

Please include the main request and response handling, useful model objects for inputs like birth details and match inputs, and clear error classes for auth, validation, rate limit, and general API errors. Make the code feel idiomatic for Ruby 2.7 plus, with a small, easy to use interface and examples that match the README.

If you need to check the current API docs or best Ruby patterns online, go ahead and look them up.