[Bugfix] Fix yt-dlp illegal write issue that causes failure to fetch source details (#247)

* Bandaid fix for yt-dlp write issue

* Ensured tempfile directory on app boot

lib/pinchflat/boot/pre_job_startup_tasks.ex

@@ -31,6 +31,7 @@ defmodule Pinchflat.Boot.PreJobStartupTasks do
   """
   @impl true
   def init(state) do
+    ensure_tmpfile_directory()
     reset_executing_jobs()
     create_blank_yt_dlp_files()
     create_blank_user_script_file()
@@ -39,6 +40,14 @@ defmodule Pinchflat.Boot.PreJobStartupTasks do
     {:ok, state}
   end
 
+  defp ensure_tmpfile_directory do
+    tmpfile_dir = Application.get_env(:pinchflat, :tmpfile_directory)
+
+    if !File.exists?(tmpfile_dir) do
+      File.mkdir_p!(tmpfile_dir)
+    end
+  end
+
   # If a node cannot gracefully shut down, the currently executing jobs get stuck
   # in the "executing" state. This is a problem because the job runner will not
   # pick them up again