Replaced instances of `.extend([item])` with `.append(item)` in multiple files.
Using `.extend([item])` incurs memory overhead by allocating a new single-element
list and is computationally slower than calling `.append(item)` directly.
Files updated:
- fastdeploy/input/encodings/ernie_encoding.py
- fastdeploy/input/ernie4_5_vl_processor/process.py
- fastdeploy/output/token_processor.py
- fastdeploy/worker/gpu_model_runner.py
- fastdeploy/worker/metax_model_runner.py