add trial_prospects table migration (#6508)

Author: ukutaht

priv/repo/migrations/20260617120000_create_trial_prospects.exs

@@ -0,0 +1,24 @@
+defmodule Plausible.Repo.Migrations.CreateTrialProspects do
+  use Ecto.Migration
+
+  def change do
+    create table(:trial_prospects) do
+      add :team_id, references(:teams, on_delete: :delete_all), null: false
+      add :estimated_monthly, :integer, null: false
+      add :observed_days, :integer, null: false
+      add :first_data_day, :date, null: false
+      add :kind, :string, null: false
+
+      add :forced_by, {:array, :string}, null: false, default: []
+      add :pageview_limit, :integer
+      add :over_top_tier, :boolean, null: false, default: false
+      add :estimated_mrr, :integer
+      add :computed_at, :utc_datetime, null: false
+
+      timestamps()
+    end
+
+    create unique_index(:trial_prospects, [:team_id])
+    create index(:trial_prospects, [:estimated_mrr])
+  end
+end