Italian localization - Additions and updates

Update de_DE.json

Update KR translation

More strings in the Extensions tab

prototype interrupt api

Extend extras image cache key with upscale_first arg

Added "--clip-models-path" switch

Allow TI training using 6GB VRAM when xformers is available

Add PNG info to pngs only if option is enabled.

Caused error in latest pytorch-lightning==1.8.0

Added translations for these Extensions/Scripts:

Dynamic Prompts
Alpha Canvas
Artists to study
Aesthetic Score

Added a few missing translations and corrected some others. Updated to the latest Extension management tool version.

While I was able to translate in the statistics the text "Time taken:" because the timing itself is a separate label, I couldn't do the same with the labels "Torch active/reserved: 3881/3892 MiB" and "Sys VRAM: 4859/8192 MiB (59.31%)" because the values (memory, percentage) are embedded in the labels (or perhaps I am not enough acknowledged to be sure I am doing it right simply translating the text).

make save dir if save dir is not exists

Correct before image saved callback

add some more classes to safety module for an extension

Unload sd_model before loading the other to solve the issue #3449

feat: add app started callback

Certain step counts for DDIM cause out of bounds error

Localization Italian - Updates and additions

Removed "Peso dei bordi del punto focale" duplicated string from "Focal point edges weight"

Deleted it_IT localization file outside localization folder as it was not intentionally committed

Added translations of the new Extensions tab, and a few corrections to some previously translated descriptions/terms.

Add Extension Manager strings

Since it's fixed and working I'm updating the translations