fix: add missing __init__.py to avoid ModuleNotFoundError on infer module

[haru2503]

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PR Type:

• Bug fix

Description

• This pull request fixes a ModuleNotFoundError when running training/preprocessing scripts using python -m ....

• The error occurs because Python does not recognize certain subdirectories as packages unless they contain an init.py file.

Example error:

(venv) PS D:\rvc\Retrieval-based-Voice-Conversion-WebUI> python infer/modules/train/preprocess.py ../wav 44100 2 ../processed_data False 0.1
Traceback (most recent call last):
  File "infer/modules/train/preprocess.py", line 23, in <module>
    from infer.lib.audio import load_audio
ModuleNotFoundError: No module named 'infer.lib'

Or when using python -m:

(venv) PS D:\rvc\Retrieval-based-Voice-Conversion-WebUI> python -m infer.modules.train.preprocess
Error while finding module specification for 'infer.modules.train.preprocess' (ModuleNotFoundError: No module named 'infer.modules')

📦 What it affects:

• Adds the missing __init__.py files in the following directories:

infer/__init__.py
infer/lib/__init__.py
infer/modules/__init__.py
infer/modules/train/__init__.py

• This resolves import issues for infer.modules.train.* and improves out-of-the-box compatibility — especially for Windows users, IDE users, and people running scripts via -m.

Screenshot

• Not applicable