Added migrations, each creating a new database table

priv/repo/migrations/20250725144032_create_comments.exs

@@ -0,0 +1,20 @@
+defmodule Sukaato.Repo.Migrations.CreateComments do
+  use Ecto.Migration
+
+  def change do
+    create table(:comments) do
+      add :slug, :string
+      add :tripcode, :string
+      add :content, :text
+      add :ledit, :utc_datetime
+      add :post_id, references(:posts, on_delete: :nothing)
+      add :reply_to, references(:comments, on_delete: :nothing)
+
+      timestamps(type: :utc_datetime)
+    end
+
+    create unique_index(:comments, [:tripcode])
+    create index(:comments, [:post_id])
+    create index(:comments, [:reply_to])
+  end
+end