feat: Add 'leads' app to Django project

leads/apps.py

@@ -0,0 +1,5 @@
+from django.apps import AppConfig
+
+class LeadsConfig(AppConfig):
+    default_auto_field = 'django.db.models.BigAutoField'
+    name = 'leads'

leads/models.py

@@ -0,0 +1,3 @@
+from django.db import models
+
+# Create your models here.

leads/views.py

@@ -0,0 +1,3 @@
+from django.shortcuts import render
+
+# Create your views here.