Release v3.0.0: PDF Viewer & Editor Integration

Major Features:
- Integrated PDF viewer with zoom, page navigation, and fit modes
- PDF editor toolbar with direct access to all PDF operations
- New app branding with docico1.png icon
- ConcreteInfo theme (light & dark variants)
- Comprehensive PDF editing: merge, split, compress, rotate, delete, reorder
- Watermark, encrypt, decrypt, and permissions management
- Overwrite original file option for all PDF operations

UI Improvements:
- PDF viewer takes full screen when active (hides tabs and toolbar)
- Compact modals with reduced font sizes
- Dark theme fixes for icons and dialogs
- Save/Save As options for PDF operations
- Improved PDF toolbar theming

Technical:
- Added isPdfViewerActive state tracking
- Proper PDF document lifecycle management
- Fixed hang issues when switching between PDF and markdown
- All dependencies are open-source (MIT, Apache 2.0, BSD)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

tests/setup.js

@@ -0,0 +1,100 @@
+/**
+ * Jest Test Setup
+ * Provides mocks and utilities for PanConverter tests
+ */
+
+// Mock window.electronAPI for renderer tests
+global.window = global.window || {};
+global.window.electronAPI = {
+  send: jest.fn(),
+  on: jest.fn(() => jest.fn()), // Returns cleanup function
+  once: jest.fn(),
+  invoke: jest.fn(() => Promise.resolve(null)),
+  removeAllListeners: jest.fn(),
+  file: {
+    save: jest.fn(),
+    saveCurrent: jest.fn(),
+    setCurrent: jest.fn(),
+    saveRecent: jest.fn(),
+    clearRecent: jest.fn(),
+    rendererReady: jest.fn()
+  },
+  theme: {
+    get: jest.fn()
+  },
+  print: {
+    doPrint: jest.fn()
+  },
+  export: {
+    withOptions: jest.fn(),
+    spreadsheet: jest.fn()
+  },
+  batch: {
+    convert: jest.fn(),
+    selectFolder: jest.fn()
+  },
+  converter: {
+    convert: jest.fn(),
+    convertBatch: jest.fn()
+  },
+  headerFooter: {
+    getSettings: jest.fn(),
+    saveSettings: jest.fn(),
+    browseLogo: jest.fn(),
+    saveLogo: jest.fn(),
+    clearLogo: jest.fn()
+  },
+  page: {
+    getSettings: jest.fn(),
+    updateSettings: jest.fn(),
+    setCustomStartPage: jest.fn()
+  },
+  pdf: {
+    processOperation: jest.fn(),
+    getPageCount: jest.fn(),
+    selectFolder: jest.fn()
+  }
+};
+
+// Mock marked library
+global.window.marked = {
+  parse: jest.fn((text) => `<p>${text}</p>`),
+  setOptions: jest.fn()
+};
+
+// Mock DOMPurify
+global.window.DOMPurify = {
+  sanitize: jest.fn((html) => html)
+};
+
+// Mock highlight.js
+global.window.hljs = {
+  highlight: jest.fn((code, options) => ({ value: code })),
+  highlightAuto: jest.fn((code) => ({ value: code })),
+  getLanguage: jest.fn(() => true)
+};
+
+// Mock localStorage
+const localStorageMock = {
+  getItem: jest.fn(),
+  setItem: jest.fn(),
+  removeItem: jest.fn(),
+  clear: jest.fn()
+};
+global.localStorage = localStorageMock;
+
+// Console spy to catch unintended console logs in tests
+const originalConsoleError = console.error;
+console.error = (...args) => {
+  // Allow certain expected errors
+  const message = args[0]?.toString() || '';
+  if (message.includes('Warning:') || message.includes('React')) {
+    return;
+  }
+  originalConsoleError.apply(console, args);
+};
+
+// Cleanup after each test
+afterEach(() => {
+  jest.clearAllMocks();
+});