Fix Elixir 1.19 and OTP 28 compatibility

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: khamilowicz

.gitignore

@@ -176,4 +176,7 @@ $RECYCLE.BIN/
 # Windows shortcuts
 *.lnk
 
-# End of https://www.gitignore.io/api/c,vim,linux,macos,elixir,windows,visualstudiocode
+# End of https://www.gitignore.io/api/c,vim,linux,macos,elixir,windows,visualstudiocode
+
+# Dialyzer PLT cache
+/priv/plts/

mix.exs

@@ -40,20 +40,22 @@ defmodule Membrane.Generator.Plugin.Mixfile do
       {:membrane_raw_video_format, "~> 0.3"},
       {:membrane_audio_mix_plugin, "~> 0.16.0", only: :test},
       {:membrane_h264_ffmpeg_plugin, "~> 0.31.0", only: :test},
-      {:credo, ">= 0.0.0", only: :dev, runtime: false},
-      {:dialyxir, ">= 0.0.0", only: :dev, runtime: false},
-      {:ex_doc, ">= 0.0.0", only: :dev, runtime: false}
+      {:credo, "~> 1.7", only: :dev, runtime: false},
+      {:dialyxir, "~> 1.4", only: :dev, runtime: false},
+      {:ex_doc, "~> 0.34", only: :dev, runtime: false}
     ]
   end
 
   defp dialyzer() do
     opts = [
-      plt_local_path: "priv/plts",
-      flags: [:error_handling]
+      flags: [:error_handling],
+      plt_add_apps: [:mix, :syntax_tools]
     ]
 
     if System.get_env("CI") == "true" do
-      [plt_core_path: "priv/plts"] ++ opts
+      # Store PLTs in cacheable directory for CI
+      File.mkdir_p!(Path.join([__DIR__, "priv", "plts"]))
+      [plt_local_path: "priv/plts", plt_core_path: "priv/plts"] ++ opts
     else
       opts
     end