Store date of last civitai check for failed hashes, and have a setting to prevent rechecking it until n hours/days have passed

[brendanhoar]

Describe Issue

I tend to perform a check every time I download and install models. This often means I'm checking a few times a day, and I do have a significant number of models that 404 on civitai.com.

I propose a setting that enables the user to set a timeout value that will tell the process to skip models that were checked but 404'd within the last n hours/days.

This may speed up the scan as well, and reduce the number of constantly repeated hits on the civitai api from regular users.

B