chore: import upstream snapshot with attribution

tests/unit/code-assist-subscription.test.ts

@@ -0,0 +1,62 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import {
+  extractCodeAssistOnboardTierId,
+  extractCodeAssistSubscriptionTier,
+} from "../../open-sse/services/codeAssistSubscription.ts";
+
+test("extractCodeAssistSubscriptionTier prefers paidTier over currentTier", () => {
+  assert.equal(
+    extractCodeAssistSubscriptionTier({
+      paidTier: { id: "tier_google_one_ai_pro", name: "Google One AI Premium" },
+      currentTier: { id: "free-tier", name: "Free" },
+    }),
+    "Google One AI Premium"
+  );
+});
+
+test("extractCodeAssistSubscriptionTier uses currentTier when not ineligible", () => {
+  assert.equal(
+    extractCodeAssistSubscriptionTier({
+      currentTier: { id: "tier_pro", name: "Pro" },
+      allowedTiers: [{ id: "free-tier", isDefault: true }],
+    }),
+    "Pro"
+  );
+});
+
+test("extractCodeAssistSubscriptionTier uses restricted default when ineligible", () => {
+  assert.equal(
+    extractCodeAssistSubscriptionTier({
+      ineligibleTiers: [{ reasonCode: "POLICY" }],
+      currentTier: { id: "tier_ultra", name: "Ultra" },
+      allowedTiers: [{ id: "tier_pro", name: "Pro", isDefault: true }],
+    }),
+    "Pro (Restricted)"
+  );
+});
+
+test("extractCodeAssistOnboardTierId prefers paidTier id for onboarding", () => {
+  assert.equal(
+    extractCodeAssistOnboardTierId({
+      paidTier: { id: "tier_google_one_ai_pro" },
+      currentTier: { id: "free-tier" },
+    }),
+    "tier_google_one_ai_pro"
+  );
+});
+
+test("extractCodeAssistOnboardTierId skips currentTier when ineligible", () => {
+  assert.equal(
+    extractCodeAssistOnboardTierId({
+      ineligibleTiers: [{}],
+      currentTier: { id: "tier_ultra" },
+      allowedTiers: [{ id: "tier_pro", isDefault: true }],
+    }),
+    "tier_pro"
+  );
+});
+
+test("extractCodeAssistOnboardTierId falls back to legacy-tier", () => {
+  assert.equal(extractCodeAssistOnboardTierId({}), "legacy-tier");
+});