fix: fix resize and dragging

- AbstractShape: make bounds protected for subclass access
- STriangle: refactor resize logic
- SCircle: refactor resize logic (preserves equal dimensions)
- SText: add reasonable default bounds for hit testing

src/main/java/ovh/gasser/newshapes/shapes/SText.java

@@ -18,7 +18,8 @@ public class SText extends AbstractShape {
     private final int fontStyle;
 
     private SText(int x, int y, String text, int fontSize, String fontName, int fontStyle) {
-        super(new Rectangle(x, y, 0, 0));
+        // Initialize with a reasonable default width/height so hit testing works reliably
+        super(new Rectangle(x, y, 100, 20));
         this.text = normalizeText(text);
         this.fontSize = fontSize;
         this.fontName = fontName;