settings ui: Improve numeric stepper component interface (#36513)

This is the first step to allowing users to type into a numeric stepper
to set its value. This PR makes the numeric stepper take in a generic
type `T` where T: `NumericStepperType`

```rust
pub trait NumericStepperType:
    Display
    + Add<Output = Self>
    + Sub<Output = Self>
    + Copy
    + Clone
    + Sized
    + PartialOrd
    + FromStr
    + 'static
{
    fn default_format(value: &Self) -> String {
        format!("{}", value)
    }
    fn default_step() -> Self;
    fn large_step() -> Self;
    fn small_step() -> Self;
    fn min_value() -> Self;
    fn max_value() -> Self;
}
```

This allows setting of step sizes and min/max values as well as making
the component easier to use.

cc @danilo-leal 

Release Notes:

- N/A

---------

Co-authored-by: Mikayla Maki <mikayla.c.maki@gmail.com>
Co-authored-by: Gaauwe Rombouts <mail@grombouts.nl>

crates/ui_input/src/ui_input.rs

@@ -4,10 +4,12 @@
 //!
 //! It can't be located in the `ui` crate because it depends on `editor`.
 //!
+mod numeric_stepper;
 
 use component::{example_group, single_example};
 use editor::{Editor, EditorElement, EditorStyle};
 use gpui::{App, Entity, FocusHandle, Focusable, FontStyle, Hsla, Length, TextStyle};
+pub use numeric_stepper::*;
 use settings::Settings;
 use std::sync::Arc;
 use theme::ThemeSettings;