Update LocalProvider to manage model size dynamically and clean up build scripts

- Introduced a new attribute `_current_model_size` in `LocalProvider` to store the current model size, allowing for dynamic configuration during generation.
- Updated the `generate` method to use the current model size instead of a hardcoded value.
- Modified the `load_model` method to track the requested model size.
- Removed platform-specific extension handling from the build scripts for both CPU and CUDA providers to streamline the build process.

providers/pytorch-cuda/build.py

@@ -58,10 +58,6 @@ def build_provider():
         '--hidden-import', 'librosa',
     ])
     
-    # Platform-specific extensions
-    if platform.system() == "Windows":
-        args[2] = 'tts-provider-pytorch-cuda.exe'
-    
     args.extend([
         '--noconfirm',
         '--clean',