Fix FOV Slider + Viewmodel

[jvnpr]

[!] This PR is dependent on #1097

Description

Change the FOV slider to use the existing fov option system instead of modifying the base FOV value in gameRenderer.
Expands the slider range from 70-110 to 30-110, and makes slider values 1:1 with ticks.

Changes

Previous Behavior

The FOV slider values are not accurate compared to other platforms and causes issues when high FOV values are used.

Root Cause

Current implementation uses the gameRenderer function SetFovVal(), which changes the base FOV value used to render the game.

The slider was implemented by creating a slider with a range of 0-100, then mapping that range to 70-110. This means the slider must be moved multiple ticks to change the value by 1.

New Behavior

Switched to using the method Minecraft::GetInstance()->options->fov to adjust FOV.
Slider values are now 1:1 with ticks.

Fix Implementation

Change CMinecraftApp::ActionGameSettings() and slider implementations to use the method Minecraft::GetInstance()->options->fov to adjust FOV.

Change slider range to 0-80 instead of 0-100, change eGameSetting_FOV to store FOV as a value 0-80 corresponding to the range 30-110 instead of a value 0-100

Use SettingFixer() (from #1097) to seamlessly convert old saved settings to new format.

AI Use Disclosure

No AI was used to author these changes or pull request.

Related Issues

• Fixes [Bug] Hand FOV changes when the FOV is changed in graphics settings #655, [Suggestion] Save user-defined FOV value #666, [Bug] FOV slider is not clamped to Java Edition values #771, [Bug] FOV 110 causes everything to FLIP when sprinting? #838, et al.
• Related to Add SettingDataVersion and Introduce SettingFixer #1097, Fix FOV Slider + Viewmodel #975