Update custom file name patterns when copy files and remove problematic parameters in export (#520)

## What does this PR do?

**Type of change:** Bugfix <!-- Use one of the following: Bug fix, new
feature, new example, new tests, documentation. -->

**Overview:** 

- Update custom file name patterns when copy files in export.
- Remove problematic parameters in export for Nemotron Nano VL models
- Resolve nvbugs https://nvbugspro.nvidia.com/bug/5637594 

## Usage
<!-- You can potentially add a usage example below. -->

```python
# Add a code snippet demonstrating how to use this
```

## Testing
<!-- Mention how have you tested your change if applicable. -->

## Before your PR is "*Ready for review*"
<!-- If you haven't finished some of the above items you can still open
`Draft` PR. -->

- **Make sure you read and follow [Contributor
guidelines](https://github.com/NVIDIA/TensorRT-Model-Optimizer/blob/main/CONTRIBUTING.md)**
and your commits are signed.
- **Is this change backward compatible?**: Yes <!--- If No, explain why.
-->
- **Did you write any new necessary tests?**: Yes/No
- **Did you add or update any necessary documentation?**: Yes/No
- **Did you update
[Changelog](https://github.com/NVIDIA/TensorRT-Model-Optimizer/blob/main/CHANGELOG.rst)?**:
Yes/No <!--- Only for new features, API changes, critical bug fixes or
bw breaking changes. -->

## Additional Information
<!-- E.g. related issue. -->

---------

Signed-off-by: Zhiyu Cheng <[email protected]>

Author: Edwardf0t1

examples/llm_ptq/example_utils.py

@@ -511,10 +511,10 @@ def copy_custom_model_files(source_path: str, export_path: str, trust_remote_cod
     # Common patterns for custom model files that need to be copied
     custom_file_patterns = [
         "configuration_*.py",
-        "modeling_*.py",
+        "modeling*.py",
         "tokenization_*.py",
         "processing_*.py",
-        "image_processing_*.py",
+        "image_processing*.py",
         "feature_extraction_*.py",
         "*.json",
     ]

modelopt/torch/export/quant_utils.py

@@ -849,6 +849,11 @@ def postprocess_state_dict(state_dict: dict, maxbound: float, quantization: str
     post_state_dict = {}
 
     for key, value in state_dict.items():
+        # Skip problematic parameters for specific model architectures, e.g., Nemotron Nano VL models
+        if key == "vision_model.radio_model.summary_idxs":
+            logger.info(f"Removing problematic parameter: {key}")
+            continue
+
         # Skip keys not related to quantizers
         if (
             "output_quantizer" not in key