feat: start on AI integration

lib/bds/ai/model_modality.ex

@@ -0,0 +1,21 @@
+defmodule BDS.AI.ModelModality do
+  @moduledoc false
+
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  @primary_key false
+
+  schema "ai_model_modalities" do
+    field :provider, :string, primary_key: true
+    field :model_id, :string, primary_key: true
+    field :direction, Ecto.Enum, values: [:input, :output], primary_key: true
+    field :modality, Ecto.Enum, values: [:text, :image, :audio, :file, :tool], primary_key: true
+  end
+
+  def changeset(modality, attrs) do
+    modality
+    |> cast(attrs, [:provider, :model_id, :direction, :modality], empty_values: [nil])
+    |> validate_required([:provider, :model_id, :direction, :modality])
+  end
+end