V2: Convert Tool (#3828)

🔄 Dynamic Processing Strategies

- Adaptive routing: Same tool uses different backend endpoints based on
file analysis
- Combined vs separate processing: Intelligently chooses between merge
operations and individual file processing
- Cross-format workflows: Enable complex conversions like "mixed files →
PDF" that other tools can't handle

  ⚙️ Format-Specific Intelligence

  Each conversion type gets tailored options:
  - HTML/ZIP → PDF: Zoom controls (0.1-3.0 increments) with live preview
  - Email → PDF: Attachment handling, size limits, recipient control
  - PDF → PDF/A: Digital signature detection with warnings
  - Images → PDF: Smart combining vs individual file options

 File Architecture

  Core Implementation:
  ├── Convert.tsx                     # Main stepped workflow UI
├── ConvertSettings.tsx # Centralized settings with smart detection
├── GroupedFormatDropdown.tsx # Enhanced format selector with grouping
├── useConvertParameters.ts # Smart detection & parameter management
  ├── useConvertOperation.ts         # Multi-strategy processing logic
  └── Settings Components:
      ├── ConvertFromWebSettings.tsx      # HTML zoom controls
      ├── ConvertFromEmailSettings.tsx    # Email attachment options
├── ConvertToPdfaSettings.tsx # PDF/A with signature detection
      ├── ConvertFromImageSettings.tsx    # Image PDF options
      └── ConvertToImageSettings.tsx      # PDF to image options

 Utility Layer

  Utils & Services:
├── convertUtils.ts # Format detection & endpoint routing
  ├── fileResponseUtils.ts          # Generic API response handling
└── setupTests.ts # Enhanced test environment with crypto mocks

  Testing & Quality

  Comprehensive Test Coverage

  Test Suite:
├── useConvertParameters.test.ts # Parameter logic & smart detection
  ├── useConvertParametersAutoDetection.test.ts  # File type analysis
├── ConvertIntegration.test.tsx # End-to-end conversion workflows
  ├── ConvertSmartDetectionIntegration.test.tsx  # Mixed file scenarios
  ├── ConvertE2E.spec.ts                     # Playwright browser tests
├── convertUtils.test.ts # Utility function validation
  └── fileResponseUtils.test.ts              # API response handling

  Advanced Test Features

  - Crypto API mocking: Proper test environment for file hashing
  - File.arrayBuffer() polyfills: Complete browser API simulation
  - Multi-file scenario testing: Complex batch processing validation
- CI/CD integration: Vitest runs in GitHub Actions with proper artifacts

---------

Co-authored-by: Connor Yoh <[email protected]>
Co-authored-by: Anthony Stirling <[email protected]>

frontend/public/locales/en-US/translation.json

@@ -1567,5 +1567,51 @@
         "description": "These cookies help us understand how our tools are being used, so we can focus on building the features our community values most. Rest assured—Stirling PDF cannot and will never track the content of the documents you work with."
       }
     }
+  },
+  "convert": {
+    "files": "Files",
+    "selectFilesPlaceholder": "Select files in the main view to get started",
+    "settings": "Settings",
+    "conversionCompleted": "Conversion completed",
+    "results": "Results",
+    "defaultFilename": "converted_file",
+    "conversionResults": "Conversion Results",
+    "converting": "Converting...",
+    "convertFiles": "Convert Files",
+    "downloadConverted": "Download Converted File",
+    "convertFrom": "Convert from",
+    "convertTo": "Convert to",
+    "sourceFormatPlaceholder": "Source format",
+    "targetFormatPlaceholder": "Target format",
+    "selectSourceFormatFirst": "Select a source format first",
+    "imageOptions": "Image Options",
+    "colorType": "Color Type",
+    "color": "Color",
+    "greyscale": "Greyscale",
+    "blackwhite": "Black & White",
+    "dpi": "DPI",
+    "output": "Output",
+    "single": "Single",
+    "multiple": "Multiple",
+    "pdfOptions": "PDF Options",
+    "fitOption": "Fit Option",
+    "maintainAspectRatio": "Maintain Aspect Ratio",
+    "fitDocumentToPage": "Fit Document to Page",
+    "fillPage": "Fill Page",
+    "autoRotate": "Auto Rotate",
+    "autoRotateDescription": "Automatically rotate images to better fit the PDF page",
+    "combineImages": "Combine Images",
+    "combineImagesDescription": "Combine all images into one PDF, or create separate PDFs for each image",
+    "webOptions": "Web to PDF Options",
+    "zoomLevel": "Zoom Level",
+    "emailOptions": "Email to PDF Options",
+    "includeAttachments": "Include email attachments",
+    "maxAttachmentSize": "Maximum attachment size (MB)",
+    "includeAllRecipients": "Include CC and BCC recipients in header",
+    "downloadHtml": "Download HTML intermediate file instead of PDF",
+    "pdfaOptions": "PDF/A Options",
+    "outputFormat": "Output Format",
+    "pdfaNote": "PDF/A-1b is more compatible, PDF/A-2b supports more features.",
+    "pdfaDigitalSignatureWarning": "The PDF contains a digital signature. This will be removed in the next step."
   }
 }