add the function of setting the file name

[himetuki]

Guidelines

• I have read the Contributing Guidelines and agree to follow them.

Feature Description

I hope to add a file naming feature that allows the use of placeholders (like the ones shown in the image) and supports custom sorting of these placeholders.
For example, when downloading images from a specific user's post, all images from that post are currently placed in an auto-named folder, but the files themselves are not renamed into a human-readable format. I'd like to be able to define a filename format such as:
{artist_id} - {post} - {date} - {index}.{extension}
This way, each file would have a clear and readable name, and the order of the placeholders could be customized as needed.

Use Case

No response

Potential Challenges

No response

Feature Type

UI Improvement