feat: add subjects and tasks API, hooks, and related types

- Implemented subjects API with functions for creating, updating, and retrieving subjects, including history and bibliography.
- Added tasks API for managing user tasks, including listing and marking tasks as completed.
- Created hooks for managing AI interactions, authentication, subjects, tasks, and metadata queries.
- Established query keys for caching and managing query states.
- Introduced Supabase client and environment variable management for better configuration.
- Defined types for database and domain models to ensure type safety across the application.

src/data/hooks/useNotifications.ts

@@ -0,0 +1,49 @@
+import { useEffect } from "react";
+import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
+import { qk } from "../query/keys";
+import { notificaciones_marcar_leida, notificaciones_mias_list } from "../api/notifications.api";
+import { supabaseBrowser } from "../supabase/client";
+
+export function useMisNotificaciones() {
+  return useQuery({
+    queryKey: qk.notificaciones(),
+    queryFn: notificaciones_mias_list,
+    staleTime: 10_000,
+  });
+}
+
+/** 🔥 Opcional: realtime (si tienes Realtime habilitado) */
+export function useRealtimeNotificaciones(enable = true) {
+  const supabase = supabaseBrowser();
+  const qc = useQueryClient();
+
+  useEffect(() => {
+    if (!enable) return;
+
+    const channel = supabase
+      .channel("rt-notificaciones")
+      .on(
+        "postgres_changes",
+        { event: "*", schema: "public", table: "notificaciones" },
+        () => {
+          qc.invalidateQueries({ queryKey: qk.notificaciones() });
+        }
+      )
+      .subscribe();
+
+    return () => {
+      supabase.removeChannel(channel);
+    };
+  }, [enable, supabase, qc]);
+}
+
+export function useMarcarNotificacionLeida() {
+  const qc = useQueryClient();
+
+  return useMutation({
+    mutationFn: notificaciones_marcar_leida,
+    onSuccess: () => {
+      qc.invalidateQueries({ queryKey: qk.notificaciones() });
+    },
+  });
+}