Adds support for Zipformer transducer ASR models that use Whisper-style
features by introducing a new feature flag, parsing metadata,
and integrating per-chunk normalization.
- Introduce UseWhisperFeature in the model interface and Zipformer implementation
- Parse "feature" metadata to set the whisper flag and wire it into the recognizer
- Update feature extraction logic to handle Whisper filterbanks with early returns
* adding ebranchformer encoder
* extend surfaced FeatureExtractorConfig
- so ebranchformer feature extraction can be configured from Python
- the GlobCmvn is not needed, as it is a module in the OnnxEncoder
* clean the code
* Integrating remarks from Fangjun
* Don't reset model state and feature extractor on endpointing
* support passing decoding_method from commandline
* Add modified_beam_search to Python API
* fix C API example
* Fix style issues
