feat: add support for ocrmac OCR engine on macOS (#276)

* feat: add support for `ocrmac` OCR engine on macOS

- Integrates `ocrmac` as an OCR engine option for macOS users.
- Adds configuration options and dependencies for `ocrmac`.
- Updates documentation to reflect new engine support.

This change allows macOS users to utilize `ocrmac` for improved OCR performance and compatibility.

Signed-off-by: Suhwan Seo <nuridol@gmail.com>

* updated the poetry lock

Signed-off-by: Suhwan Seo <nuridol@gmail.com>

* Fix linting issues, update CLI docs, and add error for ocrmac use on non-Mac systems

- Resolved formatting and linting issues
- Updated `--ocr-engine` CLI option documentation for `ocrmac`
- Added RuntimeError for attempts to use `ocrmac` on non-Mac platforms

Signed-off-by: Suhwan Seo <nuridol@gmail.com>

* feat: add support for `ocrmac` OCR engine on macOS

- Integrates `ocrmac` as an OCR engine option for macOS users.
- Adds configuration options and dependencies for `ocrmac`.
- Updates documentation to reflect new engine support.

This change allows macOS users to utilize `ocrmac` for improved OCR performance and compatibility.

Signed-off-by: Suhwan Seo <nuridol@gmail.com>

* docs: update examples and installation for ocrmac support

- Added `OcrMacOptions` to `custom_convert.py` and `full_page_ocr.py` examples.
- Included usage comments and examples for `OcrMacOptions` in OCR pipelines.
- Updated installation guide to include instructions for installing `ocrmac`, noting macOS version requirements (10.15+).
- Highlighted that `ocrmac` leverages Apple's Vision framework as an OCR backend.

This enhances documentation for users working on macOS to leverage `ocrmac` effectively.

Signed-off-by: Suhwan Seo <nuridol@gmail.com>

* fix: update `ocrmac` dependency with macOS-specific marker

- Added `sys_platform == 'darwin'` marker to the `ocrmac` dependency in `pyproject.toml` to specify macOS compatibility.
- Updated the content hash in `poetry.lock` to reflect the changes.

This ensures the `ocrmac` dependency is only installed on macOS systems.

Signed-off-by: Suhwan Seo <nuridol@gmail.com>

---------

Signed-off-by: Suhwan Seo <nuridol@gmail.com>
Co-authored-by: Suhwan Seo <nuridol@gmail.com>

tests/test_e2e_ocr_conversion.py

@@ -1,3 +1,4 @@
+import sys
 from pathlib import Path
 from typing import List
 
@@ -6,6 +7,7 @@ from docling.datamodel.base_models import InputFormat
 from docling.datamodel.document import ConversionResult
 from docling.datamodel.pipeline_options import (
     EasyOcrOptions,
+    OcrMacOptions,
     OcrOptions,
     PdfPipelineOptions,
     TesseractCliOcrOptions,
@@ -59,6 +61,11 @@ def test_e2e_conversions():
         TesseractCliOcrOptions(force_full_page_ocr=True),
     ]
 
+    # only works on mac
+    if "darwin" == sys.platform:
+        engines.append(OcrMacOptions())
+        engines.append(OcrMacOptions(force_full_page_ocr=True))
+
     for ocr_options in engines:
         print(f"Converting with ocr_engine: {ocr_options.kind}")
         converter = get_converter(ocr_options=ocr_options)