[Feat] [310p] Support w8a8sc quantization method (#7075)

### What this PR does / why we need it?
New Quantization Method: Introduced support for the W8A8SC static linear
quantization scheme specifically for 310P hardware, enabling more
efficient model compression.
Refactored the save_sharded_state_310.py to avoid multi-process issue.
### Does this PR introduce _any_ user-facing change?
No
### How was this patch tested?
W8A8SC quant E2E test.

- vLLM version: v0.16.0
- vLLM main:
4034c3d32e

---------

Signed-off-by: pu-zhe <zpuaa@outlook.com>

examples/save_sharded_state_310.py

@@ -24,12 +24,15 @@ Sparse-Compress-Quantization state dict could also be saved via this script.
 
 Example usage:
 
-python save_sharded_state.py \
+python save_sharded_state_310.py \
     --model /path/to/load \
     --tensor-parallel-size 8 \
     --output /path/to/save \
     --enable-compress \
-    --compress-process-num 8
+    --compress-process-num 8 \
+    --enforce-eager \
+    --dtype float16 \
+    --quantization ascend
 
 Then, the model can be loaded with
 
@@ -140,29 +143,30 @@ def get_quant_description(json_file: str) -> dict:
     return quant_desc
 
 
-def update_quant_description(json_file: str) -> None:
+def update_quant_description(ori_json_file: str, target_json_file: str) -> None:
     """
     Update quantization types in JSON configuration file based on update mapping.
 
     Args:
-        json_file: Path to the JSON configuration file
+        ori_json_file: Path to the JSON configuration file
+        target_json_file: Path to the JSON configuration file to be saved
 
     Raises:
         FileNotFoundError: If the JSON file does not exist
         RuntimeError: If JSON parsing fails or required keys are missing
     """
-    config_path = Path(json_file)
+    config_path = Path(ori_json_file)
     try:
         with config_path.open("r", encoding="utf-8") as file:
             json_data = json.load(file)
     except (FileNotFoundError, json.JSONDecodeError) as e:
-        raise RuntimeError(f"Failed to read configuration file {json_file}: {e}")
+        raise RuntimeError(f"Failed to read configuration file {ori_json_file}: {e}")
 
     original_quant_type = json_data.get("model_quant_type")
     if not original_quant_type or original_quant_type not in QUANTIZATION_UPDATE_MAP:
         raise RuntimeError(
             f"Cannot update quantization type. "
-            f"Original type '{original_quant_type}' not found or not supported for update in {json_file}."
+            f"Original type '{original_quant_type}' not found or not supported for update in {ori_json_file}."
         )
     updated_quant_type = QUANTIZATION_UPDATE_MAP[original_quant_type]
 
@@ -175,12 +179,12 @@ def update_quant_description(json_file: str) -> None:
             updated_config[key] = value
 
     try:
-        new_file_path = config_path.parent / "quant_model_description.json"
+        new_file_path = Path(target_json_file)
         with new_file_path.open("w", encoding="utf-8") as file:
             json.dump(updated_config, file, indent=2, ensure_ascii=False)
-        os.remove(json_file)
+        os.remove(ori_json_file)
     except OSError as e:
-        raise RuntimeError(f"Failed to write updated configuration to {json_file}: {e}")
+        raise RuntimeError(f"Failed to write updated configuration to {target_json_file}: {e}")
 
 
 def weight_compress_worker(file_path: str, quant_desc: dict, process_num: int) -> bool:
@@ -214,9 +218,6 @@ def weight_compress_worker(file_path: str, quant_desc: dict, process_num: int) -
         compressor.run()
         if p.exists():
             os.remove(p)
-        ori_quant_desc_file = p.parent / "quant_model_description.json"
-        if ori_quant_desc_file.exists():
-            os.rename(str(ori_quant_desc_file), str(ori_quant_desc_file.parent / "ori_quant_model_description.json"))
         compressor.export_safetensors(str(p.parent), safetensors_name=p.name)
         return True
     except Exception as e:
@@ -248,6 +249,10 @@ def main(args):
     # 4. Compression Logic
     parameters_map_fpath = output_dir / "parameters_type_map.json"
     if args.enable_compress:
+        quant_desc_file = output_dir / "quant_model_description.json"
+        backup_quant_desc_file = output_dir / "ori_quant_model_description.json"
+        if quant_desc_file.exists():
+            os.rename(str(quant_desc_file), str(backup_quant_desc_file))
         quant_desc = get_quant_description(str(parameters_map_fpath))
         quant_type = quant_desc["model_quant_type"]
         if quant_type in SUPPORTED_COMPRESS_QUANT_TYPE:
@@ -269,7 +274,7 @@ def main(args):
             for p in tasks:
                 p.join()
 
-            update_quant_description(os.path.join(args.output, "ori_quant_model_description.json"))
+            update_quant_description(str(backup_quant_desc_file), str(quant_desc_file))
             print("Compression completed successfully.")
         else:
             print(f"Skipping compression: Unsupported type {quant_type}")