[feature] Binary files by configurable extension (`.exe` etc) should force headers-only recheck mode

Related to https://github.com/dgtlmoon/changedetection.io/issues/2383

So for example if i add a `https://microsoft.com/really-big-download.exe` changedetection should just use the appropriate headers if they are available and not make the full request

OR make a headers request first, if no etag then continue with normal fetch?

(`.exe` , `.iso` etc)

Start by reading related issue #2383 and tracing the existing recheck behavior for large downloads. The issue names no files or tests; done should mean configurable binary extensions use headers-only checks when suitable headers exist, with a defined fallback to a normal fetch when they do not.

Written by the indexing model from the issue text.