[TensorRT EP] Enhance EP context configs in session options and provider options

[chilo-ms]

Several changes:

1. To align with other EPs' setting of EP context configs in session options, for example QNN EP, EP context configs for TRT EP can be configured through:
   1. Session Options: ep.context_enable, ep.context_file_path and ep.context_embed_mode
   2. Provider Options: trt_dump_ep_context_model, trt_ep_context_file_path and trt_dump_ep_context_embed_mode
   3. Above setting has 1:1 mapping and provider options has higher priority over session options.

    Please note that there are rules for using following context model related provider options:

     1. In the case of dumping the context model and loading the context model,
        for security reason, TRT EP doesn't allow the "ep_cache_context" node attribute of EP context node to be
        the absolute path or relative path that is outside of context model directory.
        It means engine cache needs to be in the same directory or sub-directory of context model.

     2. In the case of dumping the context model, the engine cache path will be changed to the relative path of context model directory.
        For example:
        If "trt_dump_ep_context_model" is enabled and "trt_engine_cache_enable" is enabled,
           if "trt_ep_context_file_path" is "./context_model_dir",
           - if "trt_engine_cache_path" is "" -> the engine cache will be saved to "./context_model_dir"
           - if "trt_engine_cache_path" is "engine_dir" -> the engine cache will be saved to "./context_model_dir/engine_dir"

2. User can decide the naming of the dumped "EP context" model by using trt_ep_context_file_path, please see GetCtxModelPath() for more details.

3. Added suggested comments from [TensorRT EP] Load precompiled TRT engine file directly  #18217

[chilo-ms]

@jywu-msft @gedoensmax
Please help review it and I will add unit tests for the PR as well.

[gedoensmax]

This looks great even including the plugin change son the wrapper and the embed mode warning. Thanks !
Just want to make sure I understand the options order correctly.

[chilo-ms]

@jywu-msft @gedoensmax
TRT enforces some rules about EP context provider options, please see the updated description.

[chilo-ms]

@jywu-msft
I just updated the unit test comment and please help sign off again, thanks!