funasr-onnx-v0.4.3

## Standalone ONNX Runtime Python package

Install with:

```bash
python -m pip install --upgrade "funasr-onnx==0.4.3"
```

This is the **funasr-onnx** distribution, not a new release of the separate **funasr** toolkit. Updating funasr alone does not update these wrappers.

### Fixes delivered
- Preserve missing optional exporter dependencies as ImportError causes instead of masking them with invalid string raises.
- Retain model-download failure causes and propagate unrelated exporter import failures.
- Fail immediately with the original cause when onnxruntime cannot be imported.

These implementation fixes were already in repository source; this release makes them available in the standalone PyPI package. No recognition algorithm change is included.

### Verification
- Installed wheel and source distribution passed the actual wrapper regression suite on Python 3.11 and 3.12 in exact-head CI.
- Public PyPI wheel/sdist SHA256 match the accepted candidates; post-publication installation and error-contract tests passed on Python 3.12.
- ONNX inference remains torch-free. These checks are not an acoustic-accuracy, GPU or performance benchmark.

Both wheel and source archive are attached, with SHA256SUMS and BUILD-INFO.json. Source: signed tag at commit 5145ba3b23fde43bd847f2a078751aedb4ec54e9; PR #3690. Issue #3523 remains open for original-environment verification.

[PyPI package](https://pypi.org/project/funasr-onnx/0.4.3/) | [Main FunASR toolkit releases](https://github.com/modelscope/FunASR/releases)