GitLab

* Add config variable RAG_EMBEDDING_MODEL_AUTO_UPDATE to control update behavior
* Add RAG utils embedding_model_get_path() function to output the filesystem path in addition to update of the model using huggingface_hub
* Update and utilize existing RAG functions in main: get_embedding_model() & update_embedding_model()
* Add GUI setting to execute manual update process

In case of using bedrock with litellm import boto3 exception is raised

Generate manifest.json dynamically, using MANIFEST_NAME and
MANIFEST_SHORT_NAME from the environment.