feat: add Request_API dispatcher and internal API URLs

Replaces urllib http_client with proper Request_API class in general/request_api.py
using the requests library. Adds API_BACKOFFICE, API_COMUNICACIONES, API_DOCUMENTACION
settings pointing to Docker service names. Adds requests==2.32.3 to requirements.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/api_config/settings.py

@@ -175,6 +175,11 @@ LOGGING = {
     },
 }
 
+# --- URLs de APIs internas (via red Docker saas_network) ---
+API_BACKOFFICE = os.getenv('API_BACKOFFICE', 'http://api_backoffice:8001')
+API_COMUNICACIONES = os.getenv('API_COMUNICACIONES', 'http://api_comunicaciones:8002')
+API_DOCUMENTACION = os.getenv('API_DOCUMENTACION', 'http://api_documentacion:8003')
+
 # --- CONFIGURACIONES PERSONALIZADAS DE LA APP ---
 
 # Leemos la variable del .env (cargado previamente con load_dotenv)