GDShader documentation comments for per-instance uniform does not show in inspector

[geekley]

Tested versions

• Reproducible in v4.3.stable.mono.official [77dcf97]

System information

Godot v4.3.stable.mono - Ubuntu 24.04 LTS 24.04 - X11 - Vulkan (Forward+) - integrated Intel(R) HD Graphics 5500 (BDW GT2) - Intel(R) Core(TM) i5-5300U CPU @ 2.30GHz (4 Threads)

Issue description

Support for showing GDShader documentation comments in the inspector was added by #90161, addressing godotengine/godot-proposals#7846.
However the PR only handles regular uniform docs, not instance uniform.
I was told by @Calinou to open this:

I suggest opening an issue on the main Godot repository for this. I consider this a bug, since I'd expect per-instance uniforms to be documentable the same way.
Global uniforms don't appear in the inspector (but appear in the project settings instead), so documenting them would need a separate proposal.

Steps to reproduce

/** Should we also somehow show documentation for the whole shader file here? */
shader_type spatial;

/** [i]Already[/i] shows documentation for this per-[Material] [code]uniform[/code].
 * Supports [b]BBCode[/b] and stuff.
 */
uniform vec4 material_color : source_color = vec4(1.0, 0.5, 0.0, 1.0);

/** [i]Should[/i] show documentation for this per-[code]instance[/code] uniform.
 * Supporting [b]BBCode[/b] and stuff.
 */
instance uniform vec4 instance_color : source_color = vec4(0.0, 2.5, 0.0, 1.0);

void fragment() {
	ALBEDO = material_color.rgb;
	EMISSION = instance_color.rgb;
}

Minimal reproduction project (MRP)

N/A