Add comprehensive documentation and code comments

This commit adds extensive documentation to the Mistral OCR CLI project:

- Add API.md with detailed API response format documentation
- Add CHANGELOG.md to track version changes
- Add CONTRIBUTING.md with guidelines for contributors
- Enhance README.md with more detailed usage examples and troubleshooting
- Add proper docstrings to all Python modules and functions
- Update requirements.txt with development dependencies
- Improve setup.py with better metadata

These changes make the project more accessible to users and contributors.

mistral_ocr/commands/convert.py

@@ -5,6 +5,14 @@ import re
 from pathlib import Path
 
 def run(args):
+    """
+    Main entry point for the convert command.
+    
+    Converts OCR JSON results to Markdown format.
+    
+    Args:
+        args: Command line arguments parsed by argparse
+    """
     # If output file is specified, enable single file mode
     if args.output_file:
         args.single_file = True
@@ -13,11 +21,28 @@ def run(args):
 
 # OCR response structure classes
 class OCRResponseImage:
+    """
+    Represents an image in the OCR response.
+    
+    Attributes:
+        id (str): Unique identifier for the image
+        image_base64 (str): Base64-encoded image data
+    """
     def __init__(self, id, image_base64):
         self.id = id
         self.image_base64 = image_base64
 
 class OCRResponsePage:
+    """
+    Represents a page in the OCR response.
+    
+    Attributes:
+        index (int): Zero-based page index
+        markdown (str): Extracted text content in Markdown format
+        image (str, optional): Main page image (if available)
+        images (list): List of OCRResponseImage objects
+        dimensions (dict, optional): Page dimensions
+    """
     def __init__(self, index, markdown, image=None, images=None, dimensions=None):
         self.index = index
         self.markdown = markdown
@@ -26,6 +51,15 @@ class OCRResponsePage:
         self.dimensions = dimensions
 
 class OCRResponseMetadata:
+    """
+    Represents metadata in the OCR response.
+    
+    Attributes:
+        title (str, optional): Document title
+        author (str, optional): Document author
+        creation_date (str, optional): Document creation date
+        page_count (int, optional): Total number of pages
+    """
     def __init__(self, title=None, author=None, creation_date=None, page_count=None):
         self.title = title
         self.author = author
@@ -33,11 +67,29 @@ class OCRResponseMetadata:
         self.page_count = page_count
 
 class OCRResponse:
+    """
+    Represents the complete OCR response.
+    
+    Attributes:
+        pages (list): List of OCRResponsePage objects
+        metadata (OCRResponseMetadata): Document metadata
+    """
     def __init__(self, pages=None, metadata=None):
         self.pages = pages or []
         self.metadata = metadata or OCRResponseMetadata()
 
 def replace_image_references(content, images, include_images):
+    """
+    Replace image references in markdown content with base64 data.
+    
+    Args:
+        content (str): Markdown content with image references
+        images (list): List of OCRResponseImage objects
+        include_images (bool): Whether to include images in the output
+        
+    Returns:
+        str: Markdown content with image references replaced with base64 data
+    """
     if not include_images or not images:
         return content
     
@@ -62,6 +114,16 @@ def replace_image_references(content, images, include_images):
     return content
 
 def convert_json_to_markdown(json_file, args):
+    """
+    Convert OCR JSON results to Markdown format.
+    
+    Args:
+        json_file (str): Path to the JSON file containing OCR results
+        args: Command line arguments containing conversion options
+        
+    Raises:
+        SystemExit: If an error occurs during conversion
+    """
     try:
         # Read JSON file
         with open(json_file, 'r', encoding='utf-8') as f: