feat: OneNote-style notebooks, text fonts, and page navigation

Add notebook.json containers with multi-member pages, fix PDF text
editing (size/bold/drag/double-tap), index SidecarText in search, and
share keyboard page shortcuts plus a PDF scrubber.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/l10n/app_en.arb

@@ -237,5 +237,18 @@
   "@diagExported": { "placeholders": { "bytes": { "type": "int" } } },
   "diagExportFail": "Export failed: {error}",
   "@diagExportFail": { "placeholders": { "error": { "type": "String" } } },
-  "processingOcr": "Processing OCR…"
+  "processingOcr": "Processing OCR…",
+  "notebooksSection": "Notebooks",
+  "addBlankPage": "Blank page",
+  "importIntoNotebook": "Import into notebook",
+  "notebookMembersEmpty": "No pages yet",
+  "memberCount": "{count} items",
+  "@memberCount": {
+    "placeholders": { "count": { "type": "int" } }
+  },
+  "textFontSmall": "S",
+  "textFontMedium": "M",
+  "textFontLarge": "L",
+  "textBold": "Bold",
+  "textDragHint": "Drag to move"
 }

lib/l10n/app_localizations.dart

@@ -1153,6 +1153,66 @@ abstract class AppLocalizations {
   /// In en, this message translates to:
   /// **'Processing OCR…'**
   String get processingOcr;
+
+  /// No description provided for @notebooksSection.
+  ///
+  /// In en, this message translates to:
+  /// **'Notebooks'**
+  String get notebooksSection;
+
+  /// No description provided for @addBlankPage.
+  ///
+  /// In en, this message translates to:
+  /// **'Blank page'**
+  String get addBlankPage;
+
+  /// No description provided for @importIntoNotebook.
+  ///
+  /// In en, this message translates to:
+  /// **'Import into notebook'**
+  String get importIntoNotebook;
+
+  /// No description provided for @notebookMembersEmpty.
+  ///
+  /// In en, this message translates to:
+  /// **'No pages yet'**
+  String get notebookMembersEmpty;
+
+  /// No description provided for @memberCount.
+  ///
+  /// In en, this message translates to:
+  /// **'{count} items'**
+  String memberCount(int count);
+
+  /// No description provided for @textFontSmall.
+  ///
+  /// In en, this message translates to:
+  /// **'S'**
+  String get textFontSmall;
+
+  /// No description provided for @textFontMedium.
+  ///
+  /// In en, this message translates to:
+  /// **'M'**
+  String get textFontMedium;
+
+  /// No description provided for @textFontLarge.
+  ///
+  /// In en, this message translates to:
+  /// **'L'**
+  String get textFontLarge;
+
+  /// No description provided for @textBold.
+  ///
+  /// In en, this message translates to:
+  /// **'Bold'**
+  String get textBold;
+
+  /// No description provided for @textDragHint.
+  ///
+  /// In en, this message translates to:
+  /// **'Drag to move'**
+  String get textDragHint;
 }
 
 class _AppLocalizationsDelegate

lib/l10n/app_localizations_en.dart

@@ -588,4 +588,36 @@ class AppLocalizationsEn extends AppLocalizations {
 
   @override
   String get processingOcr => 'Processing OCR…';
+
+  @override
+  String get notebooksSection => 'Notebooks';
+
+  @override
+  String get addBlankPage => 'Blank page';
+
+  @override
+  String get importIntoNotebook => 'Import into notebook';
+
+  @override
+  String get notebookMembersEmpty => 'No pages yet';
+
+  @override
+  String memberCount(int count) {
+    return '$count items';
+  }
+
+  @override
+  String get textFontSmall => 'S';
+
+  @override
+  String get textFontMedium => 'M';
+
+  @override
+  String get textFontLarge => 'L';
+
+  @override
+  String get textBold => 'Bold';
+
+  @override
+  String get textDragHint => 'Drag to move';
 }

lib/l10n/app_localizations_zh.dart

@@ -580,4 +580,36 @@ class AppLocalizationsZh extends AppLocalizations {
 
   @override
   String get processingOcr => '正在识别文字…';
+
+  @override
+  String get notebooksSection => '笔记本';
+
+  @override
+  String get addBlankPage => '空白页';
+
+  @override
+  String get importIntoNotebook => '导入到笔记本';
+
+  @override
+  String get notebookMembersEmpty => '还没有页面';
+
+  @override
+  String memberCount(int count) {
+    return '$count 项';
+  }
+
+  @override
+  String get textFontSmall => '小';
+
+  @override
+  String get textFontMedium => '中';
+
+  @override
+  String get textFontLarge => '大';
+
+  @override
+  String get textBold => '粗体';
+
+  @override
+  String get textDragHint => '拖动移动';
 }

lib/l10n/app_zh.arb

@@ -207,5 +207,18 @@
   "@diagExported": { "placeholders": { "bytes": { "type": "int" } } },
   "diagExportFail": "导出失败：{error}",
   "@diagExportFail": { "placeholders": { "error": { "type": "String" } } },
-  "processingOcr": "正在识别文字…"
+  "processingOcr": "正在识别文字…",
+  "notebooksSection": "笔记本",
+  "addBlankPage": "空白页",
+  "importIntoNotebook": "导入到笔记本",
+  "notebookMembersEmpty": "还没有页面",
+  "memberCount": "{count} 项",
+  "@memberCount": {
+    "placeholders": { "count": { "type": "int" } }
+  },
+  "textFontSmall": "小",
+  "textFontMedium": "中",
+  "textFontLarge": "大",
+  "textBold": "粗体",
+  "textDragHint": "拖动移动"
 }