feat(web): reinforce value on subscription plan selection

Three CRO additions at the point of decision:
- Outcome-focused page subtitle ("Doğru parçayı saniyede bul …") replacing
  the purely procedural copy.
- Per-day price anchor on every plan card (≈ ₺X/gün), reframing the cost as
  a small daily number. Computed from the displayed monthly/yearly price.
- "2 ay bedava" note under the billing toggle when yearly is selected,
  making the otherwise-abstract -17% concrete (yearly = 10× monthly).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/web/src/messages/en.json

@@ -123,10 +123,12 @@
   },
   "subscription": {
     "title": "Subscription",
-    "subtitle": "Pick a plan, choose your brands, complete payment — all on one page.",
+    "subtitle": "Find the right part in seconds — pick a plan and start searching.",
     "step": "Step",
     "selected": "Selected",
     "tapToSelect": "Select",
+    "perDay": "≈ {amount}/day",
+    "yearlyFreeMonths": "2 months free with yearly billing",
     "selectExactBrands": "Please select exactly {count} brands.",
     "steps": {
       "plan": {

apps/web/src/messages/tr.json

@@ -123,10 +123,12 @@
   },
   "subscription": {
     "title": "Abonelik",
-    "subtitle": "Planını seç, markalarını belirle, ödemeni yap. Hepsi tek sayfada.",
+    "subtitle": "Doğru parçayı saniyede bul — planını seç, hemen aramaya başla.",
     "step": "Adım",
     "selected": "Seçildi",
     "tapToSelect": "Seç",
+    "perDay": "≈ {amount}/gün",
+    "yearlyFreeMonths": "Yıllık ödemede 2 ay bedava",
     "selectExactBrands": "Lütfen tam olarak {count} marka seçin.",
     "steps": {
       "plan": {

apps/web/src/routes/dashboard/subscription/__tests__/value-reinforcement.test.tsx

@@ -0,0 +1,67 @@
+/**
+ * Tests for the value-reinforcement additions:
+ *  - per-day price anchor on every plan card
+ *  - "2 months free" note shown only for yearly billing
+ *
+ * These reframe the price at the moment of decision (small daily number) and
+ * make the yearly discount concrete, per the CRO audit.
+ */
+
+import { fireEvent, render } from "@testing-library/react";
+import { vi } from "vitest";
+
+vi.mock("@/lib/i18n", () => ({
+  useTranslation: () => ({
+    t: (key: string) => key,
+    locale: "tr",
+    setLocale: vi.fn(),
+  }),
+}));
+
+vi.mock("@/lib/posthog", () => ({
+  capture: vi.fn(),
+  setPeopleProperties: vi.fn(),
+}));
+
+import {
+  BillingPeriodToggle,
+  PlanGrid,
+  plans,
+} from "@/routes/dashboard/subscription/index";
+
+describe("per-day price anchor (PlanGrid)", () => {
+  test("renders a per-day line on every plan card", () => {
+    const { container } = render(
+      <PlanGrid
+        billingPeriod="monthly"
+        selectedPlanKey={null}
+        currentPlanKey={null}
+        activeSubscription={false}
+        onSelect={vi.fn()}
+      />,
+    );
+    const perDayNodes = Array.from(container.querySelectorAll("p")).filter((p) =>
+      p.textContent?.includes("subscription.perDay"),
+    );
+    expect(perDayNodes).toHaveLength(plans.length);
+  });
+});
+
+describe("yearly free-months note (BillingPeriodToggle)", () => {
+  test("shows the free-months note when yearly is selected", () => {
+    const { container } = render(<BillingPeriodToggle period="yearly" onChange={vi.fn()} />);
+    expect(container.textContent).toContain("subscription.yearlyFreeMonths");
+  });
+
+  test("hides the free-months note for monthly billing", () => {
+    const { container } = render(<BillingPeriodToggle period="monthly" onChange={vi.fn()} />);
+    expect(container.textContent).not.toContain("subscription.yearlyFreeMonths");
+  });
+
+  test("toggling fires onChange with the chosen period", () => {
+    const onChange = vi.fn();
+    const { getByText } = render(<BillingPeriodToggle period="monthly" onChange={onChange} />);
+    fireEvent.click(getByText("common.yearly"));
+    expect(onChange).toHaveBeenCalledWith("yearly");
+  });
+});

apps/web/src/routes/dashboard/subscription/index.tsx

@@ -939,7 +939,7 @@ function StepCard({
   );
 }
 
-function BillingPeriodToggle({
+export function BillingPeriodToggle({
   period,
   onChange,
 }: {
@@ -948,7 +948,7 @@ function BillingPeriodToggle({
 }) {
   const { t } = useTranslation();
   return (
-    <div className="flex items-center justify-center gap-2">
+    <div className="flex flex-col items-center gap-2">
       <div className="inline-flex rounded-full border border-border bg-muted/50 p-1">
         {(["monthly", "yearly"] as const).map((p) => (
           <button
@@ -974,6 +974,11 @@ function BillingPeriodToggle({
           </button>
         ))}
       </div>
+      {period === "yearly" && (
+        <p className="text-xs font-medium text-primary">
+          {t("subscription.yearlyFreeMonths")}
+        </p>
+      )}
     </div>
   );
 }
@@ -1043,6 +1048,13 @@ export function PlanGrid({
                 <span className="text-xs text-muted-foreground">
                   {billingPeriod === "monthly" ? t("common.perMonth") : t("common.perYear")}
                 </span>
+                <p className="mt-0.5 text-xs text-muted-foreground">
+                  {t("subscription.perDay", {
+                    amount: formatTRY(
+                      Math.round(billingPeriod === "monthly" ? price / 30 : price / 365),
+                    ),
+                  })}
+                </p>
               </div>
               <ul className="space-y-1.5 text-xs text-foreground/85">
                 {plan.features.map((f) => (