Initial setup (first pass) (#1)

* Updated Elixir version; made phx interactive

* Added JS formatting rules

* Added yt-dlp to dockerfile

* Added a basic PR template

* Added default responses for the PR template

mix.exs

@@ -5,7 +5,7 @@ defmodule Pinchflat.MixProject do
     [
       app: :pinchflat,
       version: "0.1.0",
-      elixir: "~> 1.14",
+      elixir: "~> 1.16",
       elixirc_paths: elixirc_paths(Mix.env()),
       start_permanent: Mix.env() == :prod,
       aliases: aliases(),