fix disappearing live previews and progressbar during slow tasks

fix ui img2img scripts

Fix #9046 /sdapi/v1/txt2img endpoint not working

Change extras "scale to" to sliders

Automatically select current word when adjusting weight with ctrl+up/down

Fix CLIP FileExistsError

Add support for saving init images in img2img

perf(webui): Remove duplicate code

Add filename pattern for CLIP_stop_at_last_layers (clip skip).

Add "None" option to extra networks dropdowns

fix(extras): fix batch image processing on 'Extras\Batch Process' tab

Improve custom code script

for some extreme network conditions 20 seconds may not be enough

This also makes it work with prompts without spaces between words

This change fixes an issue where an incorrect type was passed to the PIL.Image.open() function that caused the whole process to fail.

Scope of this change is limited to only batch image processing, and it shouldn't affect other functionality.

**Describe what this pull request is trying to achieve.**

Fix https://github.com/AUTOMATIC1111/stable-diffusion-webui/issues/9046

**Environment this was tested in**

* OS: Linux
* Browser: chrome
* Graphics card: RTX 3090

Sometimes tasks take longer than 5 seconds to start,
resulting in missing progress bar and livepreviews,
so we have to keep pulling for progress a bit longer (5s -> 20s).