Refactor imports, streamline database IPC handlers, and improve offline support

- Replace absolute import paths with relative paths for consistency across files.
- Transition database operations in Electron main process to modular handlers in `ipc/book.ipc.ts` using the `createHandler` pattern.
- Update database sync service to use `window.electron.invoke()` for improved reliability and structure.
- Refactor `AddNewBookForm` to handle both online and offline book creation seamlessly.

electron/database/models/Book.ts

@@ -18,8 +18,7 @@ import fs from "fs";
 import BookRepo from "../repositories/book.repository.js";
 import Chapter, {ActChapter, ChapterContentData, ChapterProps} from "./Chapter.js";
 import UserRepo from "../repositories/user.repository.js";
-import ChapterRepo from "@/electron/database/repositories/chapter.repository";
-import {mainStyle} from "@/electron/database/models/EpubStyle";
+import ChapterRepo from "../repositories/chapter.repository.js";
 
 export interface BookProps{
     id:string;

electron/database/models/Chapter.ts

@@ -8,9 +8,9 @@ import ChapterRepo, {
     CompanionContentQueryResult,
     ChapterStoryQueryResult,
     ContentQueryResult
-} from "@/electron/database/repositories/chapter.repository";
-import System from "../System";
-import {getUserEncryptionKey} from "../keyManager";
+} from "../repositories/chapter.repository.js";
+import System from "../System.js";
+import {getUserEncryptionKey} from "../keyManager.js";
 import { generateHTML } from "@tiptap/react";
 
 export interface ChapterContent {

electron/database/models/Character.ts

@@ -2,9 +2,9 @@ import CharacterRepo, {
     AttributeResult,
     CharacterResult,
     CompleteCharacterResult
-} from "@/electron/database/repositories/character.repository";
-import System from "@/electron/database/System";
-import {getUserEncryptionKey} from "../keyManager";
+} from "../repositories/character.repository.js";
+import System from "../System.js";
+import {getUserEncryptionKey} from "../keyManager.js";
 
 export type CharacterCategory = 'Main' | 'Secondary' | 'Recurring';
 

electron/database/models/Location.ts

@@ -2,9 +2,9 @@ import LocationRepo, {
     LocationByTagResult,
     LocationElementQueryResult,
     LocationQueryResult
-} from "@/electron/database/repositories/location.repository";
-import System from "@/electron/database/System";
-import {getUserEncryptionKey} from "../keyManager";
+} from "../repositories/location.repository.js";
+import System from "../System.js";
+import {getUserEncryptionKey} from "../keyManager.js";
 
 export interface SubElement {
     id: string;

electron/database/models/User.ts

@@ -1,7 +1,7 @@
-import UserRepo, {UserAccountQuery, UserInfosQueryResponse} from "@/electron/database/repositories/user.repository";
-import System from "@/electron/database/System";
-import Book, {BookProps} from "@/electron/database/models/Book";
-import {getUserEncryptionKey} from "@/electron/database/keyManager";
+import UserRepo, {UserAccountQuery, UserInfosQueryResponse} from "../repositories/user.repository.js";
+import System from "../System.js";
+import Book, {BookProps} from "./Book.js";
+import {getUserEncryptionKey} from "../keyManager.js";
 
 interface UserAccount{
     firstName:string;