feat: Implement main application shell with navigation and color scheme toggle

- Added Appshell component with responsive navbar and main content area
- Integrated ColorSchemeToggle for light/dark mode switching
- Created Welcome component with styled title and introductory text
- Developed ChatPage for LLM interaction with WebSocket support
- Implemented Biblioteca for managing notes with rich text editor
- Added LoginPage for user authentication with error handling
- Introduced MessageList and MessageBubble components for chat messages
- Styled components with CSS modules for consistent design

domains/ApiKeys/openai_apikey.py

@@ -0,0 +1,24 @@
+from domains.Security.GenerarIDs import GeneradorIDUnico
+
+class OpenAICredencial:
+    def __init__(self, titulo: str, api_key: str, organizacion: str = None, id: str = None):
+        """
+        :param titulo: Nombre descriptivo para esta credencial.
+        :param api_key: Clave secreta de la API de OpenAI.
+        :param organizacion: (Opcional) ID de la organización asociada a la cuenta de OpenAI.
+        """
+        self.id = id if id is not None else GeneradorIDUnico("OPAK").generar()
+        self.titulo = titulo    
+        self.api_key = api_key
+        self.organizacion = organizacion
+
+    def get_headers(self) -> dict:
+        """
+        Retorna los encabezados necesarios para autenticar una petición HTTP a OpenAI.
+        """
+        headers = {
+            "Authorization": f"Bearer {self.api_key}"
+        }
+        if self.organizacion:
+            headers["OpenAI-Organization"] = self.organizacion
+        return headers