bare-low/gpt-5.4-mini / tier-2-offset-handle-mug

```openscad
$fn = 128;

module mug_body() {
    difference() {
        cylinder(h = 90, d = 80);
        translate([0, 0, 6])
            cylinder(h = 90 - 6 + 0.2, d = 70);
    }
}

module handle_2d() {
    // D-shaped profile in the X-Z plane:
    // flat side on the body, semicircle on the outside.
    outer_w = 35;
    outer_h = 40;
    inner_w = 25;
    inner_h = 30;
    cx = 57.5;
    cz = 45;

    difference() {
        union() {
            translate([40, cz - outer_h / 2])
                square([outer_w / 2, outer_h], center = false);
            translate([cx, cz])
                circle(r = outer_h / 2);
        }
        union() {
            translate([45, cz - inner_h / 2])
                square([inner_w / 2, inner_h], center = false);
            translate([cx, cz])
                circle(r = inner_h / 2);
        }
    }
}

module handle() {
    // Extrude along Y to give the handle thickness.
    // Slight overlap into the mug body ensures a robust union.
    linear_extrude(height = 16, center = true, convexity = 10)
        handle_2d();
}

union() {
    mug_body();

    // Small bridge to guarantee a solid manifold connection on the +X side.
    translate([38.5, -8, 26])
        cube([8.0, 16, 38], center = false);

    handle();
}
```