Refactor: Split COCO dataset into detection and segmentation datasets

[Chandraveersingh1717]

Summary

Split coco_detection_dataset() into two specialized datasets for object detection and instance segmentation tasks.

Problem

• Current implementation carries 500MB+ annotation object in memory for entire dataset lifetime
• Confusing documentation mixing detection and segmentation use cases
• Tasks never run together (different model architectures)
• Poor cache organization with unidentified large files

Solution

coco_detection_dataset() - Object Detection Only

• Returns: boxes, labels, area, iscrowd
• Memory: ~250MB (50% reduction)
• Use: Faster R-CNN, YOLO, SSD

coco_segmentation_dataset() - Instance Segmentation (NEW)

• Returns: boxes, labels, area, iscrowd, segmentation, masks
• Memory: ~250MB
• Use: Mask R-CNN, DeepLab

Cache Organization: Files now stored in /coco subdirectory for better identification

Breaking Change

Segmentation users must migrate:

# Before
coco_detection_dataset(..., target_transform = target_transform_coco_masks)

# After  
coco_segmentation_dataset(..., target_transform = target_transform_coco_masks)

[cregouby]

Hello @Chandraveersingh1717,

Thansk a lot for this contribution ! It actually fix #171 ! (And sorry for the delay to review it, I miss the notification)
Please give me few days to review it...

[cregouby]

Hello @Chandraveersingh1717

praise thanks a lot for this contribution
todo missing Would you add your name to the contributor list in DESCRIPTION file ?
todo documentation Documentation of the package is not up-to-date with your changes in roxygen2. Please perform a devtools::document() and resubmit Rd files
todo R CMD CHECK fails, and should be fixed.
suggestion You can see the R CMD CHECK failures in the CI/CD pipeline logs ("checks" tab in github) but you can see them performing a local devtools::check()
todo please remove all unexpected files at package top folder. (as per

❯ checking top-level files ... NOTE
Non-standard files/directories found at top level:
‘test_coco_changes.R’ ‘tiny_meta.json’ ‘tiny_meta.ndjson’
todo Please mention you are using a LLM if any in the NEWS

[cregouby]

todo please do not remove actual news

[cregouby]

Thanks a lot !