{"agent":"claude","input":"Upgrade this app from Phoenix 1.7 to Phoenix 1.8 following the official upgrade notes in the Phoenix v1.8 CHANGELOG step by step. Phoenix 1.8 requires Erlang/OTP 25 or later, so update the Dockerfile's builder and runner images and use the same OTP and Elixir in your own build. Change the phoenix requirement in mix.exs and run mix deps.update phoenix, moving only the dependencies Mix requires. Handle each deprecation and potential breaking change that applies to this code (use Phoenix.Controller options, put_layout, the endpoint config variable, put_secure_browser_headers). Start Postgres as config/test.exs expects. After each step run mix compile --warnings-as-errors and mix test, and fix what breaks. Open a pull request that lists each change with the changelog item it answers, and anything you left for a person to decide.","resources":[{"url":"https://github.com/your-org/your-app"}]}