Show IES shape in OpenGL 3D view

The goal would be something like this:

It can be implemented as a draw handler.
Example code:

import bpy
from bgl import *

def draw_callback():
    # As an example, draw a red line from world coordinates (0, 0, 0) to (1, 1, 1)
    glColor3f(1.0, 0.0, 0.0)
    glLineWidth(2.0)
    
    glBegin(GL_LINES)
    glVertex3f(0.0, 0.0, 0.0)
    glVertex3f(1.0, 1.0, 1.0)
    glEnd()
    
def register():
    # The arguments for the draw_callback function, in our case no arguments
    args = ()
    bpy.types.SpaceView3D.draw_handler_add(draw_callback, args, 'WINDOW', 'POST_VIEW')
    
def unregister():
    bpy.types.SpaceView3D.draw_handler_remove(draw_callback, 'WINDOW')

if __name__ == "__main__":
    register()

See also this stackoverflow question.
Here is a proof-of-concept of these types of custom widgets: https://github.com/LuxCoreRender/BlendLuxCore/commit/f8c784462b58e1db3216e1e8ecd0ff5f8312e6de#diff-6408ff2ba505ecbce1cec82283fb7070R60

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Start by searching the repository for IES handling and any existing Blender viewport drawing entry points. Review bpy.types.SpaceView3D.draw_handler_add and the linked proof of concept, then verify the implementation displays the IES shape in the OpenGL 3D view for the relevant light. Done means the shape appears as in the provided preview without disrupting the view.