docs: Add Bedrock model builder example notebooks

Add notebooks demonstrating Bedrock deployment workflows:
- bedrock-modelbuilder-deployment-nova.ipynb: Nova model deployment
  via BedrockModelBuilder with SFTTrainer fine-tuning
- boto3_deployment_notebook.ipynb: Direct boto3 Bedrock deployment
- model_builder_deployment_notebook(1).ipynb: ModelBuilder deployment
- 07-ml-model-development(1).ipynb: ML model development workflow
- sagemaker-serve/example_notebooks/bedrock_nova_deployment.ipynb:
  Clean Nova deployment example with polling, inference, and cleanup

Author: nargokul