[Docs] Model_doc structure/clarity improvements (#26876)

* first batch of structure improvements for model_docs

* second batch of structure improvements for model_docs

* more structure improvements for model_docs

* more structure improvements for model_docs

* structure improvements for cv model_docs

* more structural refactoring

* addressed feedback about image processors

docs/source/en/model_doc/vision-encoder-decoder.md

@@ -151,20 +151,32 @@ were contributed by [ydshieh](https://github.com/ydshieh).
 
 [[autodoc]] VisionEncoderDecoderConfig
 
+<frameworkcontent>
+<pt>
+
 ## VisionEncoderDecoderModel
 
 [[autodoc]] VisionEncoderDecoderModel
     - forward
     - from_encoder_decoder_pretrained
 
+</pt>
+<tf>
+
 ## TFVisionEncoderDecoderModel
 
 [[autodoc]] TFVisionEncoderDecoderModel
     - call
     - from_encoder_decoder_pretrained
 
+</tf>
+<jax>
+
 ## FlaxVisionEncoderDecoderModel
 
 [[autodoc]] FlaxVisionEncoderDecoderModel
     - __call__
     - from_encoder_decoder_pretrained
+
+</jax>
+</frameworkcontent>