Crescent Orbital Megastructure

Create a cinematic hard-science-fiction space scene showing an enormous crescent-shaped orbital megastructure above {argument name="planet" default="Earth"}. The structure is a dark metallic incomplete ring, shaped like a giant curved arc or broken crescent, with intricate layered panels, exposed trusses, scaffolding, antennae, docking spines, and thin mechanical ribs. At its center is a small glowing spherical hub with warm amber light, connected to the crescent by exactly three long articulated support arms, plus one separate small curved module floating near the hub. The megastructure should feel massive, industrial, and partially under construction, with subtle orange running lights along the frame and cold white highlights on black gunmetal surfaces. Below, the bright curved horizon of Earth fills the lower third of the image, covered in pale clouds and atmospheric haze, while the upper two thirds are deep black space with sparse tiny stars. Use a vertical 4:5 composition, wide-angle orbital perspective, dramatic scale, realistic lighting, high contrast, photorealistic rendering, cinematic concept art detail, no text, no watermark, no visible astronauts or spacecraft.