Refactor output area and mask handling for flexible canvas bounds

This update introduces a unified output area bounds system, allowing the output area to be extended in all directions independently of the custom shape. All mask and layer operations now reference outputAreaBounds, ensuring correct alignment and rendering. The mask tool, mask editor, and export logic have been refactored to use these bounds, and a new UI for output area extension with live preview and tooltips has been added. The code also improves logging and visualization of mask and output area boundaries.

src/types.ts

@@ -136,6 +136,13 @@ export interface Shape {
     isClosed: boolean;
 }
 
+export interface OutputAreaBounds {
+    x: number;      // Pozycja w świecie (może być ujemna)
+    y: number;      // Pozycja w świecie (może być ujemna)  
+    width: number;  // Szerokość output area
+    height: number; // Wysokość output area
+}
+
 export interface Viewport {
     x: number;
     y: number;