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/useAI.ts

@@ -0,0 +1,28 @@
+import { useMutation } from "@tanstack/react-query";
+import {
+  ai_plan_chat,
+  ai_plan_improve,
+  ai_subject_chat,
+  ai_subject_improve,
+  library_search,
+} from "../api/ai.api";
+
+export function useAIPlanImprove() {
+  return useMutation({ mutationFn: ai_plan_improve });
+}
+
+export function useAIPlanChat() {
+  return useMutation({ mutationFn: ai_plan_chat });
+}
+
+export function useAISubjectImprove() {
+  return useMutation({ mutationFn: ai_subject_improve });
+}
+
+export function useAISubjectChat() {
+  return useMutation({ mutationFn: ai_subject_chat });
+}
+
+export function useLibrarySearch() {
+  return useMutation({ mutationFn: library_search });
+}