[Feature Request] Extended Max Framerate slider limit and custom cap override #585

Description
With high-refresh-rate monitors becoming more and more common, the vanilla 250 FPS limit on the frame rate slider forces players with high refresh rate monitors to go straight into the "Unlimited" setting. It would be a good QoL feature to extend the vanilla Max Framerate slider to support higher frame rate caps and finer step adjustments, and arbitrary higher limits.

My suggestion

• Change the slider increment step from vanilla's 10 FPS to 5 FPS for more precise settings like 165,175,185 FPS
• Provide an option to allow players to set an exact target beyond vanilla's limit of 250 FPS (e.g., capping precisely at 310 FPS).