Optimize ensure vertical feature's UX

[SoftFever]

The previous user experience was somewhat confusing, particularly with the settings for ensure_vertical_shell_thickness and reduce_wall_solid_infill.

This PR improves the UI and refines the functionality of these options:

1. Changed ensure_vertical_shell_thickness to an enum value type to simplify selection and improve clarity.
2. Introduced an option to completely disable this feature, giving users more control over their printing preferences.
   

@igiannakas FYI. The 'Critical Only" is same as this combination you added in this PR #3235.

[igiannakas]

Excellent refactor, makes so much more sense now!

is the none a desired option though? This will break vertical slopes, so needs to be used carefully I suppose? Also I think this impacts top surfaces even if not sloped? Haven’t run the build yet so apologies if it doesn’t :)

Maybe the tool tip needs to say that it’s not suitable for any models with sloped surfaces?

[SoftFever]

Excellent refactor, makes so much more sense now!

is the none a desired option though? This will break vertical slopes, so needs to be used carefully I suppose? Also I think this impacts top surfaces even if not sloped? Haven’t run the build yet so apologies if it doesn’t :)

Maybe the tool tip needs to say that it’s not suitable for any models with sloped surfaces?

The use case of "None" that I can think of is for SpeedBenchy or people only want to verify a design as quick as possible

Updating warn user in the tooltip is a good idea. Let me add one

[igiannakas]

Awesome 👏🏻👌🏻

[SoftFever]

Merged.