fix: resolve audio lip sync not working issue

[LoS-Light]

🐞 Issue

Audio lip sync is not working after the release "Cubism 5 SDK for Unity R4".

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🔁 Steps to Reproduce

1. Create a new Unity project.
2. Download the latest SDK from the official website and import it.
3. Open the scene Live2D/Cubism/Samples/Animation/Animation.unity.
4. Follow the official tutorial to configure the components:
   [https://docs.live2d.com/en/cubism-sdk-tutorials/lipsync/]
5. Play the scene — you will notice that the audio plays, but the model’s mouth does not move.

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🛠️ Cause & Fix

The issue is caused by an incorrect parameter being passed in the following method:
174b795#diff-27d85b246b2b472ef331fc967de9266d893d4afcfd945823c9829f51230f17f2

File: CubismParameterExtensionMethods.cs
Line: 152

Following change will fix the issue:

- self[i].OverrideValue(self[i].Value, weight);
+ self[i].OverrideValue(value, weight);

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Thank you very much for your great work and support

[wada-at-live2d-com]

@LoS-Light

Thank you for creating the pull request!
We apologize for the delayed response.

We have confirmed the fix and would like to incorporate this PR.
It is scheduled to be reflected in the product at a later date.

Thank you for your contribution.