Fix Detectron2LayoutModel import path in docs

Updates lp.Detectron2LayoutModel to lp.models.Detectron2LayoutModel
in modelzoo.md and index.rst examples.

From: Layout-Parser#202 (firesh), Layout-Parser#198 (drewm23)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: IgorTavcar

docs/example/deep_layout_parsing/index.rst

@@ -29,7 +29,7 @@ Use Layout Models to detect complex layout
 
 .. code:: python
 
-    model = lp.Detectron2LayoutModel('lp://PubLayNet/faster_rcnn_R_50_FPN_3x/config', 
+    model = lp.models.Detectron2LayoutModel('lp://PubLayNet/faster_rcnn_R_50_FPN_3x/config', 
                                      extra_config=["MODEL.ROI_HEADS.SCORE_THRESH_TEST", 0.8],
                                      label_map={0: "Text", 1: "Title", 2: "List", 3:"Table", 4:"Figure"})
         # Load the deep layout model from the layoutparser API 

docs/notes/modelzoo.md

@@ -6,7 +6,7 @@ We provide a spectrum of pre-trained models on different datasets.
 
 ```python
 import layoutparser as lp
-model = lp.Detectron2LayoutModel(
+model = lp.models.Detectron2LayoutModel(
             config_path ='lp://PubLayNet/faster_rcnn_R_50_FPN_3x/config', # In model catalog
             label_map   ={0: "Text", 1: "Title", 2: "List", 3:"Table", 4:"Figure"}, # In model`label_map`
             extra_config=["MODEL.ROI_HEADS.SCORE_THRESH_TEST", 0.8] # Optional
@@ -42,4 +42,4 @@ model.detect(image)
 | [PrimaLayout](https://www.primaresearch.org/dataset/)        | `{1:"TextRegion", 2:"ImageRegion", 3:"TableRegion", 4:"MathsRegion", 5:"SeparatorRegion", 6:"OtherRegion"}` |
 | [NewspaperNavigator](https://news-navigator.labs.loc.gov/)        | `{0: "Photograph", 1: "Illustration", 2: "Map", 3: "Comics/Cartoon", 4: "Editorial Cartoon", 5: "Headline", 6: "Advertisement"}` |
 | [TableBank](https://doc-analysis.github.io/tablebank-page/index.html)         | `{0: "Table"}` |
-| [MFD](http://transcriptorium.eu/~htrcontest/MathsICDAR2021/)         | `{1: "Equation"}` |
+| [MFD](http://transcriptorium.eu/~htrcontest/MathsICDAR2021/)         | `{1: "Equation"}` |