Refactor Dockerfile.ci to use precompiled VLLM installation and remove unused parse.py file. Update serving_chat.py to streamline rendering logic and enhance compatibility with new API. Modify OmniInputPreprocessor to directly handle SingletonDictPrompt, improving input processing efficiency.

Signed-off-by: tzhouam <tzhouam@connect.ust.hk>

docs/api/README.md

@@ -31,7 +31,6 @@ Input data structures for multi-modal inputs.
 - [vllm_omni.inputs.data.OmniTextPrompt][]
 - [vllm_omni.inputs.data.OmniTokenInputs][]
 - [vllm_omni.inputs.data.OmniTokensPrompt][]
-- [vllm_omni.inputs.parse.parse_singleton_prompt_omni][]
 - [vllm_omni.inputs.preprocess.OmniInputPreprocessor][]
 
 ## Engine