- Add File parameter class in openapi/params.py with binary format schema
- Implement comprehensive multipart/form-data parsing in openapi_validation.py
  * Support for WebKit and standard boundary formats
  * Base64-encoded request handling for AWS Lambda
  * Mixed file and form data parsing
- Update dependant.py to handle File parameters in body field resolution
- Add comprehensive test suite (13 tests) covering:
  * Basic file upload parsing and validation
  * WebKit boundary format support
  * Base64-encoded multipart data
  * Multiple file uploads
  * File size constraints validation
  * Optional file parameters
  * Error handling for invalid boundaries and missing files
- Add file_parameter_example.py demonstrating various File parameter use cases
- Clean up unnecessary imports and pragma comments

Resolves file upload functionality with full OpenAPI schema generation and validation support.

- Break down _parse_multipart_data method into smaller helper methods
- Reduce cognitive complexity from 43 to under 15 per SonarCloud requirement
- Improve code readability and maintainability
- All existing tests continue to pass

Helper methods created:
- _decode_request_body: Handle base64 decoding
- _extract_boundary_bytes: Extract multipart boundary
- _parse_multipart_sections: Parse sections into data dict
- _parse_multipart_section: Handle individual section parsing
- _split_section_headers_and_content: Split headers/content
- _decode_form_field_content: Decode form field as string

Addresses SonarCloud cognitive complexity violation while maintaining
all existing functionality for File parameter multipart parsing.

- Add FastAPI-inspired UploadFile class with filename, content_type, size, headers properties
- Enhance multipart parser to extract and preserve file metadata from Content-Disposition headers
- Implement automatic type resolution for backward compatibility with existing bytes-based File parameters
- Add comprehensive Pydantic schema validation for UploadFile class
- Include 6 comprehensive test cases covering metadata access, backward compatibility, and file reconstruction scenarios
- Update official example to showcase both new UploadFile and legacy bytes approaches
- Maintain 100% backward compatibility - existing bytes code works unchanged
- Address @leandrodamascena feedback about file reconstruction capabilities in Lambda environments

Fixes: File parameter enhancement for metadata access in AWS Lambda file uploads

…_to_args

- Extract helper functions to reduce cognitive complexity from 24 to under 15
- _get_field_location: Extract field location logic
- _get_field_value: Extract value retrieval logic with error handling
- _resolve_field_type: Extract Union type resolution logic
- _convert_value_type: Extract UploadFile/bytes conversion logic
- Maintain all existing functionality and test coverage
- Improve code readability and maintainability