DeepseekVL add local_repo_path argument AND infer support delete truncation_strategy

[starxhong]

PR type

• [ ] Bug Fix
• [Y ] New Feature
• [ ] Document Updates
• [ ] More Models or Datasets Support

PR information

1，DeepseekVL needs clone repo from github at runtime now. Whereas, in case of network unreached or some custom changes to DeepseekVL，a local repo may be need. 'local_repo_path' argument is added here. 2，Infer with input length exceeds the max_length will raise an ValueError now, which is NOT we usually expect. when truncation_strategy is 'delete'，just return a empty repsonse seems more friendly.

Experiment results

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