fix(web,api): lecteur — worker pdf.js dédié, shell commun et préférences par livre

Régression worker PDF : le worker pdf.js est désormais instancié une
seule fois via un port dédié (?worker&url) et reconfiguré à chaque
montage, au lieu d'un workerSrc recalculé qui cassait le rendu.

- ReaderShell : chrome commun aux lecteurs (toolbar, zones de tap,
  statut) et contrat ReaderControls pour EPUB/PDF/CBZ
- préférences de lecture par livre (mode horizontal/vertical, fit) :
  table reader_preferences + migrations idempotentes, module API,
  DTO partagés, client web avec fallback localStorage hors-ligne

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/api/src/database/database.service.ts

@@ -143,6 +143,7 @@ export class DatabaseService implements OnModuleDestroy {
     `);
     this.ensureBooksSupportsComicArchives();
     this.ensureBooksMetadataColumns();
+    this.ensureReaderPreferencesTable();
     this.ensureMetadataSourceConfigColumns();
     this.ensureAutomationSettingsColumns();
     this.ensureMetadataDefaults();
@@ -235,6 +236,22 @@ export class DatabaseService implements OnModuleDestroy {
     this.sqlite.exec("CREATE INDEX IF NOT EXISTS books_isbn13_idx ON books(isbn13)");
   }
 
+  private ensureReaderPreferencesTable(): void {
+    this.sqlite.exec(`
+      CREATE TABLE IF NOT EXISTS reader_preferences (
+        id INTEGER PRIMARY KEY AUTOINCREMENT,
+        user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+        book_id INTEGER NOT NULL REFERENCES books(id) ON DELETE CASCADE,
+        mode TEXT NOT NULL CHECK (mode IN ('paged','scrolled','horizontal','vertical')),
+        fit TEXT CHECK (fit IN ('page','width','height','auto')),
+        created_at TEXT NOT NULL,
+        updated_at TEXT NOT NULL,
+        UNIQUE(user_id, book_id)
+      );
+      CREATE INDEX IF NOT EXISTS reader_preferences_user_idx ON reader_preferences(user_id);
+    `);
+  }
+
   private ensureMetadataSourceConfigColumns(): void {
     const names = this.columnNames("metadata_source_config");
     const now = sqlString(this.now());

apps/api/src/database/schema.ts

@@ -50,6 +50,24 @@ export const books = sqliteTable(
   (table) => ({ filePathIdx: uniqueIndex("books_file_path_unique").on(table.filePath) })
 );
 
+export const readerPreferences = sqliteTable(
+  "reader_preferences",
+  {
+    id: integer("id").primaryKey({ autoIncrement: true }),
+    userId: integer("user_id")
+      .notNull()
+      .references(() => users.id, { onDelete: "cascade" }),
+    bookId: integer("book_id")
+      .notNull()
+      .references(() => books.id, { onDelete: "cascade" }),
+    mode: text("mode", { enum: ["paged", "scrolled", "horizontal", "vertical"] }).notNull(),
+    fit: text("fit", { enum: ["page", "width", "height", "auto"] }),
+    createdAt: text("created_at").notNull(),
+    updatedAt: text("updated_at").notNull()
+  },
+  (table) => ({ userBookIdx: uniqueIndex("reader_preferences_user_book_unique").on(table.userId, table.bookId) })
+);
+
 export const progress = sqliteTable(
   "progress",
   {