fix file uploads, serve them properly, put behind auth wall, decrypt secret message in frontend

lib/entendu_web/uploaders/encrypted_link.ex

@@ -31,14 +31,14 @@ defmodule Entendu.EncryptedLink do
   # end
 
   # Override the persisted filenames:
-  # def filename(version, _) do
-  #   version
-  # end
+  def filename(_version, {_file, %{filename: filename}}) do
+    if filename, do: filename, else: "text"
+  end
 
   # Override the storage directory:
-  # def storage_dir(version, {file, scope}) do
-  #   "uploads/user/avatars/#{scope.id}"
-  # end
+  def storage_dir(version, {_file, scope}) do
+    "uploads/links/#{scope.id}"
+  end
 
   # Provide a default URL if there hasn't been a file uploaded
   # def default_url(version, scope) do