feat: add TeleChat4 model support

[cbxgovo]

What does this PR do?

This PR adds initial TeleChat4 support to LLaMA-Factory.

Changes

• Add initial TeleChat4 model support to LLaMA-Factory.
• Add TeleChat4 chat template and model registration.
• Add TeleChat4-specific model loading and compatibility logic.
• Extend model configuration and model engine handling for TeleChat4.
• Update the English and Chinese README documentation to include TeleChat4 support.

Testing

• Successfully completed TeleChat4 LoRA fine-tuning with the modified LLaMA-Factory codebase.
• The fine-tuning process completed successfully using a TeleChat4 LoRA training configuration.
• Verified model loading, chat template handling, and LoRA fine-tuning integration.

Before submitting

• Did you read the contributor guideline?
  yes
• Did you write any new necessary tests?
  The implementation has been functionally validated through an end-to-end TeleChat4 LoRA fine-tuning run. No additional automated test cases have been introduced in this PR.