Limiting Photo stacks

No, it will not work in your case. Your shutter speed varies too much and it will be nearly impossible for Lightroom to be able to accurately stack your images. I've tried and tried, believe me. Manually is the way to go.

See the Auto Stack command of the Any Source plugin, which provides much more flexibility with stacking.  You can tell it to stack every n photos. You can also tell it if your camera records capture time at the beginning or the end of the exposure (LR assumes it’s always it’s the start of the exposure and thus can incorrectly stack brackets with long-exposure photos). 

Looking at your screenshot again, I think the problem is when you shoot HDR indoor. The outdoor series all stack correctly. Because indoor series will take more time (the brightest shots will have a fairly long shutter speed), you will have to increase the time interval for the auto stacking from 3 seconds to perhaps 5 seconds. That still should not be a problem at all, as long as you remember not to try to take two HDR series within that same time frame.

Visual similarity, like John suggested, may indeed help, but you do risk getting stacks of different images, because some images are quite similar. I would try that as last resort; it should not be necessary.

Plugins are not allowed to stack photos in the catalogue.

Try using the Visual Similarity setting in conjunction with the Capture Time.

I don’t think there is any plugin like that. How do you make your HDR brackets? Most cameras can do this in burst, so the time between brackets is really small. For example: if your camera can shoot at 5fps, then it should be able to do a five brackets HDR in one second (unless the shutter speeds are getting quite long). So as long as you do not make two HDRs within one or two seconds (which is unlikely, but simply take your time between HDR series), auto stacking on capture time should work perfectly.