kit: Dev server hangs for 1-2min+ when lots of small files in project directory

Is your feature request related to a problem? Please describe. I added ~80mb worth of tiny files (small icon .pngs and .jsons) to my static assets paths. When dev server started, the first request took ~2 minutes to complete. After that it was usually ok for a while, but sometimes this 2min delay reoccurred, making developing on the npm run dev very difficult

I am not 100% sure what the cause of this problem was. I suspect it is the file watcher of the dev server, but it could be something else. I read some source code and it seems like cheap-watch is being used to watch files on the disk. I never found a reference to this watcher in the documentation, and there is no way to configure it from svelte.config.cjs. There is the Vite config, which in turn passes some options to a chokidar package (which is the watcher that Vite uses), and some people in the Discord seemed to think that I should change my Vite config to add the files to the ignore list. When I played around with these configs, it seemed to have no effect at all, and me finding out about cheap-watch seems to support my theory that cheap-watch is indeed the one watching my files.

I solved the problem by moving my static assets outside my project root, to a sibling directory.

Describe the solution you’d like Watch files based on a watched_dirs glob whitelist (do not watch anything unless explicitly told so) in svelte.config.cjs along with sane defaults, or watch everything in the local directory, but add user configurable ignored list of globs to ignore.

Also, as a sidenote, it would be nice to have some kind of --verbose option for the dev server, so when you’re running it you’d know what’s taking so long for it to respond.

Describe alternatives you’ve considered One solution is to completely ignore the configured assets path on dev server, although this would of course have the side effect of not triggering the watcher when static assets are modified. But since no one solution fits everyone, I’d like this to be configurable with a configuration option.

Or, just optimize the file watcher so well that it can easily handle tens of thousands of small files without the server hanging.

How important is this feature to you? For now, I can make do with moving my static assets to a sibling directory of the project directory, so I am able to move on, but I spent plenty of hours debugging this, so improvements would be very good in order to attract people who don’t want to dive into source code to debug.