Docling >=0.50 vs == 0.49 breaks for images in tables

When upgrading from 0.49 to 0.50 I observe a change in the behaviour from docling.

This change seems to be much more impactful than just switching to the new Heron model. See below

Input is (preview here - full document below)

## For 0.49 the result is

### With Heron

Image detected but no longer correctly referenced.

No longer parsable with heuristics afterwards.

### Without Heron

Image correctly detected and classified and referenced.

However a bit distorting the table structure (but still parsable with sufficient heuristics) afterwards.

## For 0.50 the result is

### With Heron

Image is not there anymore, even the image classification is missing; no hotfix afterwards/heuristics possible

### Without Heron

Image is not there anymore, even the image classification is missing; no hotfix afterwards/heuristics possible

> NOTICE: This is independent of heron (the major change that happend)

So what is going on?

See the code to reproduce (plus attached dat file).

You have to install/change the library versions accordingly as needed.

Model download and imports

```python
from docling_core.types.doc.document import DoclingDocument
from docling_core.types.io import DocumentStream
from pypdf import PdfReader

import psutil
from docling.datamodel.accelerator_options import AcceleratorDevice, AcceleratorOptions
from docling.datamodel.base_models import InputFormat
from docling.datamodel.document import ConversionResult
from docling.datamodel.pipeline_options import (
RapidOcrOptions,
TableFormerMode,
ThreadedPdfPipelineOptions
)
from docling.document_converter import DocumentConverter, PdfFormatOption

import os
from pathlib import Path

import requests
import torch
from docling.utils.model_downloader import download_models
from huggingface_hub import hf_hub_download

from modelscope import snapshot_download
from tqdm import tqdm
# from wand.image import Image as WImage
from IPython.display import display, HTML

from docling.datamodel.pipeline_options import LayoutOptions
from docling.datamodel.layout_model_specs import DOCLING_LAYOUT_HERON, DOCLING_LAYOUT_V2
from docling.models.layout_model import LayoutModel
from docling_core.types.doc import ImageRefMode

DEFAULT_CACHE_DIR = Path.home() / ".cache"
CACHE_DIR = Path(os.getenv("MODEL_CACHE_DIR", DEFAULT_CACHE_DIR))
PADDLEOCR_MODELS_PATH = CACHE_DIR / "paddleocr_v4_native"

hf_model_path = CACHE_DIR / "huggingface/hub"
modelscope_model_path = CACHE_DIR / "modelscope/hub"

hf_model_path.mkdir(parents=True, exist_ok=True)
modelscope_model_path.mkdir(parents=True, exist_ok=True)

rapidocr_models_root = str(modelscope_model_path / "RapidAI/RapidOCR/onnx")

def download_modelscope(model_id, model_revision, cache_dir, allow_patterns):
print("--- Starting Filtered Model Download ---")
print(f"Model ID: {model_id}")
print(f"Revision: {model_revision}")
print(f"Target Directory: {cache_dir}")
print(f"Allow Patterns: {allow_patterns}")
print("--------------------------------------")

local_model_path = snapshot_download(
model_id=model_id,
revision=model_revision,
cache_dir=cache_dir,
allow_patterns=allow_patterns,
)
print("\n✅ Model downloaded successfully!")
print(f"Model files are located at: {local_model_path}")

rapidocr_model_files = [
"configuration.json",
"onnx/PP-OCRv5/det/ch_PP-OCRv5_server_det.onnx",
"onnx/PP-OCRv5/rec/latin_PP-OCRv5_rec_mobile_infer.onnx",
"onnx/PP-OCRv4/cls/ch_ppocr_mobile_v2.0_cls_infer.onnx",
"resources/fonts/FZYTK.TTF",
]
download_modelscope(
model_id="RapidAI/RapidOCR",
model_revision="v3.4.0",
cache_dir=modelscope_model_path,
allow_patterns=rapidocr_model_files,
)

download_models(progress=True, with_easyocr=False)

LayoutModel.download_models(
local_dir=hf_model_path / DOCLING_LAYOUT_V2.model_repo_folder,
force=False,
progress=True,
)
```
document parser

```python
def setup_ocr(model_spec=None):
physical_cores = psutil.cpu_count(logical=False)
usable_cores = max(2, physical_cores)

IMAGE_RESOLUTION_SCALE = 4

pipeline_options = ThreadedPdfPipelineOptions()
pipeline_options.do_ocr = True
pipeline_options.images_scale = IMAGE_RESOLUTION_SCALE
pipeline_options.generate_page_images = False
pipeline_options.do_picture_classification = True
pipeline_options.generate_picture_images = True

det_model_path = os.path.join(
rapidocr_models_root, "PP-OCRv5/det/ch_PP-OCRv5_server_det.onnx"
)
rec_model_path = os.path.join(
rapidocr_models_root, "PP-OCRv5/rec/latin_PP-OCRv5_rec_mobile_infer.onnx"
)
cls_model_path = os.path.join(
rapidocr_models_root, "PP-OCRv4/cls/ch_ppocr_mobile_v2.0_cls_infer.onnx"
)
rec_font_path = os.path.join(rapidocr_models_root, "resources/fonts/FZYTK.TTF")

pipeline_options.ocr_options = RapidOcrOptions(
det_model_path=det_model_path,
rec_model_path=rec_model_path,
cls_model_path=cls_model_path,
rec_font_path=rec_font_path,
)

pipeline_options.do_table_structure = True
pipeline_options.table_structure_options.do_cell_matching = True
pipeline_options.table_structure_options.mode = TableFormerMode.ACCURATE
pipeline_options.ocr_options.lang = ["en"]

pipeline_options.accelerator_options = AcceleratorOptions(
num_threads=usable_cores, device=AcceleratorDevice.AUTO
)

if model_spec:
doc_converter = DocumentConverter(
format_options={
InputFormat.PDF: PdfFormatOption(
pipeline_options=pipeline_options,
layout_options=LayoutOptions(model_spec=model_spec)
),
}
)
else:
doc_converter = DocumentConverter(
format_options={
InputFormat.PDF: PdfFormatOption(
),
}
)
return doc_converter
```

With Heron

```python
input_path = 'WO2024040109-eval-small'

doc_converter = setup_ocr(model_spec=DOCLING_LAYOUT_HERON)
conv_res = doc_converter.convert(f'{input_path}.pdf')
conv_res.document.save_as_html(f"{input_path}.html")
display(HTML(conv_res.document.export_to_html()))
```

Without Heron

```python
input_path = 'WO2024040109-eval-small'

doc_converter = setup_ocr(model_spec=DOCLING_LAYOUT_V2)
conv_res = doc_converter.convert(f'{input_path}.pdf')
conv_res.document.save_as_html(f"{input_path}_old.html")
display(HTML(conv_res.document.export_to_html()))
```

The document which was used for this testing is

[WO2024040109-eval-small.pdf](https://github.com/user-attachments/files/22197268/WO2024040109-eval-small.pdf)