[Feature Request] Option to handle "Sync to exact content frame rate" automatically, depending on the display refresh rate.

This should be a very convenient feature for those who use RetroArch with multiple screens but also useful for new users who don't know when to enable/disable this.

In my case, i have two screens, one 240hz freesync/gsync monitor and a regular 60hz TV. I switch very often between the two, depending on where i sit.

The problem is, "Sync to exact content frame rate" must always switch to ON or OFF when i change screens because:

A) If the feature is ON, there are random frame drops and stutters in the regular TV but runs smoothly on the fast monitor.
B) If the feature is OFF, it runs smoothly on the TV but the scrolling is inconsistent on the 240hz monitor.

So every time i switch, i have to change this option too, manually. There is no option that will make it run smoothly on both so it's a mandatory step. Now, there is a hotkey that was added for this but it turns out changing it this way doesn't work 100% correctly. I think RA needs to be restarted for this to be optimal.

So my suggestion is this: If RetroArch can detect the current refresh rate of the screen (not the content) could it also enable/disable this feature automatically? In 99% of cases there is no reason for this option to be OFF if your screen is 120/144/240hz and there is no reason to have this ON if you use a regular, non VRR 60hz screen. There may be some cases though, like a 60hz monitor that is also VRR (i have never seen one but i know they exist). And maybe someone doesn't want this option to be forced even if they have a fast VRR screen, for performance reasons. So maybe this automatic switch could be optional.

This isn't only useful for multi-screen setups or users who know when to switch this ON/OFF. It also ensures that RA will run smoothly on the vast majority of monitors/TVs, regardless of user input/knowledge so it's also good for new users who may or may not have a VRR screen.

Start by reviewing RetroArch’s existing “Sync to exact content frame rate” option and how it detects the active display’s refresh rate. Define the optional automatic behavior for 60 Hz, high-refresh, and VRR screens, including display switching, then verify that the setting changes reliably without requiring a restart.