V2 Tauri integration (#3854)

# Description of Changes

Please provide a summary of the changes, including:

## Add PDF File Association Support for Tauri App

  ### 🎯 **Features Added**
  - PDF file association configuration in Tauri
  - Command line argument detection for opened files
  - Automatic file loading when app is launched via "Open with"
  - Cross-platform support (Windows/macOS)

  ### 🔧 **Technical Changes**
  - Added `fileAssociations` in `tauri.conf.json` for PDF files
  - New `get_opened_file` Tauri command to detect file arguments
  - `fileOpenService` with Tauri fs plugin integration
  - `useOpenedFile` hook for React integration
  - Improved backend health logging during startup (reduced noise)

  ### 🧪 **Testing**
See 
* https://v2.tauri.app/start/prerequisites/
*
[DesktopApplicationDevelopmentGuide.md](DesktopApplicationDevelopmentGuide.md)

  ```bash
  # Test file association during development:
  
  cd frontend
  npm install
  cargo tauri dev --no-watch -- -- "path/to/file.pdf"
  ```

 For production testing:
  1. Build: npm run tauri build
  2. Install the built app
  3. Right-click PDF → "Open with" → Stirling-PDF

  🚀 User Experience

- Users can now double-click PDF files to open them directly in
Stirling-PDF
- Files automatically load in the viewer when opened via file
association
  - Seamless integration with OS file handling

---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing)
for more details.

---------

Co-authored-by: Connor Yoh <[email protected]>
Co-authored-by: James Brunton <[email protected]>
Co-authored-by: James Brunton <[email protected]>

frontend/vitest.config.ts

@@ -2,45 +2,52 @@ import { defineConfig } from 'vitest/config';
 import react from '@vitejs/plugin-react-swc';
 import tsconfigPaths from 'vite-tsconfig-paths';
 
-// When DISABLE_ADDITIONAL_FEATURES is false (or unset), enable proprietary features
-const isProprietary = process.env.DISABLE_ADDITIONAL_FEATURES !== 'true';
+export default defineConfig((configEnv) => {
+  const isProprietary = process.env.DISABLE_ADDITIONAL_FEATURES !== 'true';
+  const isDesktopMode =
+    configEnv.mode === 'desktop' ||
+    process.env.STIRLING_DESKTOP === 'true' ||
+    process.env.VITE_DESKTOP === 'true';
 
-export default defineConfig({
-  plugins: [
-    react(),
-    tsconfigPaths({
-      projects: [
-        isProprietary ? './tsconfig.proprietary.json' : './tsconfig.core.json',
+  const baseProject = isProprietary ? './tsconfig.proprietary.json' : './tsconfig.core.json';
+  const desktopProject = isProprietary ? './tsconfig.desktop.json' : baseProject;
+  const tsconfigProject = isDesktopMode ? desktopProject : baseProject;
+
+  return {
+    plugins: [
+      react(),
+      tsconfigPaths({
+        projects: [tsconfigProject],
+      }),
+    ],
+    test: {
+      globals: true,
+      environment: 'jsdom',
+      setupFiles: ['./src/core/setupTests.ts'],
+      css: false, // Disable CSS processing to speed up tests
+      include: [
+        'src/**/*.{test,spec}.{js,mjs,cjs,ts,mts,cts,jsx,tsx}'
       ],
-    }),
-  ],
-  test: {
-    globals: true,
-    environment: 'jsdom',
-    setupFiles: ['./src/core/setupTests.ts'],
-    css: false, // Disable CSS processing to speed up tests
-    include: [
-      'src/**/*.{test,spec}.{js,mjs,cjs,ts,mts,cts,jsx,tsx}'
-    ],
-    exclude: [
-      'node_modules/',
-      'src/**/*.spec.ts', // Exclude Playwright E2E tests
-      'src/tests/test-fixtures/**'
-    ],
-    testTimeout: 10000, // 10 second timeout
-    hookTimeout: 10000, // 10 second timeout for setup/teardown
-    coverage: {
-      reporter: ['text', 'json', 'html'],
       exclude: [
         'node_modules/',
-        'src/core/setupTests.ts',
-        '**/*.d.ts',
-        'src/tests/test-fixtures/**',
-        'src/**/*.spec.ts' // Exclude Playwright files from coverage
-      ]
+        'src/**/*.spec.ts', // Exclude Playwright E2E tests
+        'src/tests/test-fixtures/**'
+      ],
+      testTimeout: 10000, // 10 second timeout
+      hookTimeout: 10000, // 10 second timeout for setup/teardown
+      coverage: {
+        reporter: ['text', 'json', 'html'],
+        exclude: [
+          'node_modules/',
+          'src/core/setupTests.ts',
+          '**/*.d.ts',
+          'src/tests/test-fixtures/**',
+          'src/**/*.spec.ts' // Exclude Playwright files from coverage
+        ]
+      }
+    },
+    esbuild: {
+      target: 'es2020' // Use older target to avoid warnings
     }
-  },
-  esbuild: {
-    target: 'es2020' // Use older target to avoid warnings
-  }
+  };
 });