test(e2e): add paid voice insufficient credits flow

e2e/fixtures/test-data.ts

@@ -207,6 +207,60 @@ export const paidImageUnlockHistoryResponse = {
   messageIds: [paidImageMessageId],
 };
 
+export const paidVoiceMessageId = "msg_voice_paywall_001";
+export const paidVoiceAudioUrl =
+  "data:audio/mpeg;base64,//uQZAAAAAAAAAAAAAAAAAAAAAAAWGluZwAAAA8AAAACAAACcQCA";
+
+export const paidVoiceHistoryResponse = {
+  messages: [
+    {
+      role: "assistant",
+      type: "voice",
+      content: "",
+      id: paidVoiceMessageId,
+      created_at: "2026-07-01T00:00:00.000Z",
+      audioUrl: paidVoiceAudioUrl,
+      image: {
+        type: null,
+        url: null,
+      },
+      lockDetail: {
+        locked: true,
+        showContent: true,
+        showUpgrade: true,
+        reason: "voice_message",
+        hint: "Unlock this voice message with credits.",
+        detail: null,
+      },
+    },
+  ],
+  total: 1,
+  limit: 50,
+  offset: 0,
+  isVip: false,
+  privateFreeLimit: 0,
+  privateUsedToday: 0,
+  privateCanViewFree: false,
+};
+
+export const insufficientCreditsUnlockVoiceResponse = {
+  unlocked: false,
+  content: "",
+  reason: "insufficient_balance",
+  creditBalance: 3,
+  creditsCharged: 0,
+  requiredCredits: 20,
+  shortfallCredits: 17,
+  lockDetail: {
+    locked: true,
+    showContent: true,
+    showUpgrade: true,
+    reason: "voice_message",
+    hint: "Unlock this voice message with credits.",
+    detail: null,
+  },
+};
+
 export const paymentPlansResponse = {
   plans: [
     {