fix(nui/core): keep cursor clipping when no cursor is present

[tens0rfl0w]

Goal of this PR

This PR addresses an issue where the mouse cursor is not clipped to the game window when a NUI is focused without the cursor being present (i.e., only the keyboard is focused). This behavior causes the cursor to move outside the game frame in non-fullscreen mode or when using a multi-monitor setup, leading to loss of focus while moving the game camera.

How is this PR achieving the goal

The proposed change introduces a check for the presence of a cursor (g_hasCursor). Game frame clipping is now disabled only when a cursor is actively present, ensuring camera movement still works as intended.

This PR applies to the following area(s)

FiveM

Successfully tested on

Game builds: Not applicable

Platforms: Windows (Client)

Checklist

• Code compiles and has been tested successfully.
• Code explains itself well and/or is documented.
• My commit message explains what the changes do and what they are for.
• No extra compilation warnings are added by these changes.

Fixes issues

Reported by myself here: https://forum.cfx.re/t/5172373