Shading language hint_range for uniform variables doesn't round to step

### Tested versions

Reproducible in: v4.5.stable.official [876b29033]
I think this is unlikely to be a recent regression.

### System information

Windows 11 - Godot v4.5.stable.official [876b29033] - Vulkan (Forward+)

### Issue description

Following uniform definition:
`uniform float spread : hint_range(-1.0, 1.0, 0.1) = 0.0;`
Modifying the value in the inspector causes the parameter to be not rounded to 0.0 anymore but is set to something like 0.0000000149012 and it is not possible to set to exactly 0.0 anymore.
With `uniform float spread : hint_range(0.0, 1.0, 0.1) = 0.0;` it sets the value to 0.0 as expected.

### Steps to reproduce

- Define a uniform variable in a shader: `uniform float spread : hint_range(-1.0, 1.0, 0.1) = 0.0;`
- Assign shader to any material and change the Shader Parameters in the Inspector to any value and then back to 0.0 (or any other value)

### Minimal reproduction project (MRP)

[mrp.zip](https://github.com/user-attachments/files/23810350/mrp.zip)

Start by opening the attached MRP and reproducing the issue with the shader uniform in the Inspector. Trace how the Inspector edits `hint_range` values for the shader parameter, then verify that returning to 0.0 or another step value produces the exact stepped value rather than a small floating-point remainder.

Written by the indexing model from the issue text.