Allow grid corners to be dragged outside image bounds

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

public/views/grid-setup.mjs

@@ -152,10 +152,7 @@ export class Grid_Setup {
 		const sp = this.#screen_pos(e);
 		if (this.#drag_idx !== -1) {
 			const img_pos = this.#world_to_img(this.#to_world(sp));
-			this.#corners[this.#drag_idx] = {
-				x: Math.max(0, Math.min(this.#img.width,  img_pos.x)),
-				y: Math.max(0, Math.min(this.#img.height, img_pos.y)),
-			};
+			this.#corners[this.#drag_idx] = img_pos;
 			this.#draw();
 		} else if (this.#panning) {
 			this.#cam_x += sp.x - this.#pan_last.x;