fix(goals): drop no-target-date goals from the on-track denominator

The KPI tile reads 'X of Y on track'. Y was every active goal minus
reached + paused, which included open-ended goals (no target_date).
But an open-ended goal has no required monthly pace to compare
against — by definition it can be neither on track nor behind. Counting
it in the denominator dragged the ratio down and never improved as the
user kept saving (the fraction stays stuck because the open-ended goal
is never a hit).

Exclude :no_target_date from tracked_total. Numerator unchanged. The
subline still surfaces 'N without a deadline' as informational so the
user knows those goals exist.

test/controllers/goals_controller_test.rb

@@ -176,6 +176,23 @@ class GoalsControllerTest < ActionDispatch::IntegrationTest
     assert_match(/1\s*reached/i, response.body)
   end
 
+  test "index KPI 'on track' denominator excludes no-target-date goals" do
+    family = users(:family_admin).family
+    family.goals.destroy_all
+    # One trackable goal (has target_date) + one open-ended (no target_date).
+    # The trackable one should be the only thing in the denominator;
+    # open-ended goals can't be off pace because they have no required pace.
+    build_goal(family, "House", target_amount: 1_000_000, target_date: 1.year.from_now)
+    build_goal(family, "Emergency", target_amount: 1_000_000, target_date: nil)
+
+    get goals_url
+    assert_response :success
+    # Expect "0 of 1" — the open-ended goal stays out of the fraction
+    # even though it's active.
+    assert_match(/0\s*of\s*1/i, response.body)
+    assert_match(/without a deadline/i, response.body)
+  end
+
   private
     def build_goal(family, name, target_amount: 1_000_000, target_date: nil)
       g = family.goals.new(name: name, target_amount: target_amount, target_date: target_date, currency: "USD")