iter-png-1/gpt-5.4 / tier-2-offset-handle-mug

```openscad
$fn = 128;

// Mug dimensions
outer_d   = 80;
inner_d   = 70;
mug_h     = 90;
bottom_t  = 6;

// Handle inner opening dimensions
handle_open_w = 25;   // width in radial (X) direction
handle_open_h = 30;   // height in Z direction

// Handle thickness
handle_wall = 5;

// Derived mug radii
outer_r = outer_d / 2;
inner_r = inner_d / 2;

// Handle dimensions
handle_outer_w = handle_open_w + handle_wall;   // D-shape total width (straight side to farthest point)
handle_outer_h = handle_open_h + 2 * handle_wall;

handle_inner_r = handle_open_h / 2;
handle_outer_r = handle_outer_h / 2;

handle_center_z = mug_h / 2;

// Slight overlap into mug body to guarantee manifold union
attach_overlap = 1.0;

// 2D D-shape in XZ plane:
// left side is the straight attachment side, right side is the semicircular outer side
module d2d(x_left, z_center, total_w, total_h) {
    r = total_h / 2;
    union() {
        square_w = total_w - r;
        translate([x_left, z_center - r])
            square([square_w, total_h], center = false);
        translate([x_left + square_w, z_center])
            circle(r = r);
    }
}

module mug_body() {
    difference() {
        cylinder(h = mug_h, r = outer_r);
        translate([0, 0, bottom_t])
            cylinder(h = mug_h - bottom_t + 0.01, r = inner_r);
    }
}

module handle() {
    difference() {
        // Outer handle body
        linear_extrude(height = handle_outer_h, center = true)
            d2d(outer_r - attach_overlap, handle_center_z, handle_outer_w + attach_overlap, handle_outer_h);

        // Inner finger opening
        linear_extrude(height = handle_open_h, center = true)
            d2d(outer_r + handle_wall, handle_center_z, handle_open_w, handle_open_h);
    }
}

union() {
    mug_body();
    handle();
}
```