Initial yt-dlp implementation (#3)

* Added basic runner for yt-dlp commands

* Updated formatting rules

* Added JSON runner; Added test script for CLI interactions

* Reworked yt-dlp runner; added proper test mocks

config/test.exs

@@ -1,14 +1,18 @@
 import Config
 
+config :pinchflat,
+  # Specifying backend data here makes mocking and local testing SUPER easy
+  yt_dlp_executable: Path.join([File.cwd!(), "/test/support/scripts/yt-dlp-mocks/repeater.sh"])
+
 # Configure your database
 #
 # The MIX_TEST_PARTITION environment variable can be used
 # to provide built-in test partitioning in CI environment.
 # Run `mix help test` for more information.
 config :pinchflat, Pinchflat.Repo,
-  username: "postgres",
-  password: "postgres",
-  hostname: "localhost",
+  username: System.get_env("POSTGRES_USER"),
+  password: System.get_env("POSTGRES_PASSWORD"),
+  hostname: System.get_env("POSTGRES_HOST"),
   database: "pinchflat_test#{System.get_env("MIX_TEST_PARTITION")}",
   pool: Ecto.Adapters.SQL.Sandbox,
   pool_size: 10