fix(chat): expose actionable provider errors

scripts/phase1-auth-smoke.mjs

@@ -302,7 +302,10 @@ try {
       assert.equal(missingAiSettings.response.status, 400, `Missing AI key must fail: ${pathname}`);
     }
     const chatBody = {
+      id: "phase7-client-chat",
       sessionId: "phase7-chat",
+      trigger: "submit-message",
+      messageId: "phase7-user-message",
       messages: [{
         id: "phase7-user-message",
         role: "user",
@@ -315,6 +318,29 @@ try {
       body: JSON.stringify(chatBody),
     });
     assert.equal(anonymousChat.status, 401, "Anonymous chat request must fail");
+
+    const invalidChatRequest = await fetch(`${baseUrl}/api/chat`, {
+      method: "POST",
+      headers: {
+        "content-type": "application/json",
+        cookie: ownerCookie,
+        origin: baseUrl,
+      },
+      body: JSON.stringify({
+        id: "phase7-invalid-chat",
+        sessionId: "phase7-chat",
+        trigger: "submit-message",
+        messages: [],
+      }),
+    });
+    assert.equal(invalidChatRequest.status, 400);
+    assert.equal(invalidChatRequest.headers.get("x-neta-error-code"), "VALIDATION_ERROR");
+    assert.match(
+      await invalidChatRequest.text(),
+      /"messages" alanı boş olamaz/,
+      "Chat validation errors must identify the invalid request field",
+    );
+
     const missingChatSettings = await fetch(`${baseUrl}/api/chat`, {
       method: "POST",
       headers: {
@@ -325,6 +351,11 @@ try {
       body: JSON.stringify(chatBody),
     });
     assert.equal(missingChatSettings.status, 400, "Missing AI key must fail: /api/chat");
+    assert.match(
+      await missingChatSettings.text(),
+      /AI sağlayıcısı ve API anahtarı/,
+      "The AI SDK v6 transport envelope must pass request validation and reach provider settings",
+    );
     assert.equal(
       db.prepare("select count(*) as value from chat_messages where session_id = ?")
         .get("phase7-chat").value,

scripts/phase7-backend-boundary.mjs

@@ -46,6 +46,44 @@ if (/\bapiKey\b|\bprovider\b/.test(chatPage)) {
   violations.push("app/(dashboard)/chat/page.tsx: AI secret/provider leaked to browser code");
 }
 
+const chatRoute = fs.readFileSync(
+  path.join(process.cwd(), "app/api/chat/route.ts"),
+  "utf8",
+);
+for (const transportField of ['id:', 'trigger:', 'messageId:']) {
+  assert.ok(
+    chatRoute.includes(transportField),
+    `Chat request schema must accept AI SDK v6 transport field ${transportField}`,
+  );
+}
+for (const diagnosticMarker of [
+  "describeRequestIssues",
+  "x-neta-error-code",
+  "geçerli bir JSON gövdesi",
+  "her mesaj id, role ve parts",
+]) {
+  assert.ok(
+    chatRoute.includes(diagnosticMarker),
+    `Chat route is missing diagnostic marker: ${diagnosticMarker}`,
+  );
+}
+
+const aiProvider = fs.readFileSync(
+  path.join(process.cwd(), "server/ai/provider.ts"),
+  "utf8",
+);
+for (const providerDiagnostic of [
+  "APICallError",
+  "API anahtarını reddetti",
+  "kullanım limiti aşıldı",
+  "modeli sağlayıcıda bulunamadı",
+]) {
+  assert.ok(
+    aiProvider.includes(providerDiagnostic),
+    `AI provider diagnostics are missing: ${providerDiagnostic}`,
+  );
+}
+
 assert.deepEqual(
   violations,
   [],