QoL: Add auto perspective

[Noisyfox]

This PR introduces auto perspective that works similar to Blender:

• When click the top/bottom/left/right/front/back on the 3D navigator, or switch to those view from the menu, or by shortcuts (Ctrl+1-6), the camera automatically switch to orthogonal view
• When switch to any other angles, either by dragging with mouse/track pad, or by clicking other non-perpendicular faces on 3D navigator, or select default view from menu/short cut (Ctrl+0), the camera automatically switch to perspective view
• Panning and scalling won't trigger the view change
• This is optional and disabled by default, you can enable this from the view menu
  

This PR also fixes a few issues with 3D navigator:

• When click top/bottom view, sometimes the orientation is wrong. Now the orientation is always the same as if you select the top/bottom view from the view menu or by the shortcut.
• When dragging the 3d navigator vertically, once the vertical limit is reached and you keep dragging it, the view will keep fliping diagonally (gimbal lock, techenically). This issue is illustrated as below, and has been fixed in this PR and the orientation is stable.

Fix #7848

[discip]

Great! 😃👍

Again a much appreciated QoL addition! 🚀

Thank you so much for all the fixes and improvements! ❤

[yw4z]

Nice work on navigator. FYI there is a small glitch when using corners one after another. you can see few times appearing on first half of video

orca-slicer_U0eRqjqopU.mp4

i thought auto perspective was changing field of view (FOV) depends on total area for plates

here is orthographic view

here is perspective looks too much. i thing there should be equation like zoom_amount / FOV = 1 . perspective also should reduce while zoom out

[Noisyfox]

FYI there is a small glitch when using corners one after another.

That might because the cursor get moved a little bit right after clicking the corner, which will stop the animation. Shouldn't be a huge problem though.

[Noisyfox]

i thought auto perspective was changing field of view (FOV) depends on total area for plates

It should behave the same as changing perspective from the view menu manually.

[yw4z]

do yo have any plans to reducing fov. that looks too exaggerated. offtopic but also objects disappears from viewport if i move a bit further from bed

[Noisyfox]

do yo have any plans to reducing fov. that looks too exaggerated. offtopic but also objects disappears from viewport if i move a bit further from bed

I'll raise a separate PR for fixing this.