fix: Add output buffer cleansing in Response::json and enhance error logging for conversation parsing

backend/app/Core/Response.php

@@ -54,7 +54,11 @@ class Response
         $this->sendHeaders();
         http_response_code($this->statusCode);
 
-        echo json_encode($data, JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT);
+        if (ob_get_length()) {
+            ob_clean();
+        }
+
+        echo json_encode($data, JSON_UNESCAPED_UNICODE);
         exit;
     }
 

backend/app/Views/TeacherPortal.php

@@ -668,21 +668,33 @@ class TeacherPortal
                 const res = await fetch('/api/chat/conversations', {
                     headers: { 'Authorization': 'Bearer ' + token }
                 });
-                const data = await res.json();
+                const text = await res.text();
+                let data;
+                try {
+                    data = JSON.parse(text);
+                } catch (jsonErr) {
+                    console.error('Conversations parse error:', jsonErr, 'Raw:', text);
+                    const container = document.getElementById('conv_list_container');
+                    if (container) {
+                        container.innerHTML = '<div style="padding: 20px; text-align: center; color: #F87171; font-size: 12px;">خطأ في معالجة البيانات</div>';
+                    }
+                    return;
+                }
+
                 if (res.ok && data.status === 'success') {
-                    renderConversations(data.data);
+                    renderConversations(data.data || []);
                 } else {
-                    console.warn('Load convs returned:', data);
+                    console.warn('Load convs returned error payload:', data);
                     const container = document.getElementById('conv_list_container');
                     if (container) {
                         container.innerHTML = '<div style="padding: 20px; text-align: center; color: var(--text-muted); font-size: 12px;">' + (data.message || 'لا توجد محادثات نشطة') + '</div>';
                     }
                 }
             } catch (e) {
-                console.error('Load convs error:', e);
+                console.error('Load convs network error:', e);
                 const container = document.getElementById('conv_list_container');
                 if (container) {
-                    container.innerHTML = '<div style="padding: 20px; text-align: center; color: #F87171; font-size: 12px;">تعذر تحميل المحادثات (خطأ في الاتصال)</div>';
+                    container.innerHTML = '<div style="padding: 20px; text-align: center; color: #F87171; font-size: 12px;">تعذر تحميل المحادثات</div>';
                 }
             }
         }