Added NSFW tag support

[TolgaYigit]

Added NSFW builtin tag and blur option on image preview
#511 #279

[zanllp]

Thank you for your contribution to the IIB! The feature you added is indeed very useful. However, I have a concern regarding the automatic downloading of the detection model during startup.

For a significant portion of our users, this functionality may not be necessary. Many users run IIB via Docker or installation scripts on cloud servers, where an immediate, lightweight experience is crucial. Automatically downloading the ONNX detection model could hinder that, especially since some regions may face network issues when trying to download the model.

I recommend considering an initialization of the model only when needed, which would enhance the user experience for those who do not require this feature.

I apologize for the delay in providing more detailed feedback; I’ve been quite busy this week. I’ll take a closer look at the PR as soon as I can.