fix: Power of Two touch response + lighter colors + canvas position

- Touch coordinate conversion: remove incorrect dpr division,
  use scaleX/scaleY from canvas logical-to-CSS ratio
- Canvas create(): remove absolute positioning that broke clicks
- Colors lightened: bg #e8f0f8, text #444/#558/#889

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

app/src/main/assets/console.js

@@ -931,18 +931,10 @@ class SymjaConsole {
                     const ch = h || panel.clientHeight || window.innerHeight;
                     c.width = cw * dpr;
                     c.height = ch * dpr;
-                    // CSS 精确填充
-                    Object.assign(c.style, {
-                        width: cw + 'px',
-                        height: ch + 'px',
-                        maxWidth: '100%',
-                        maxHeight: '100%',
-                        objectFit: 'contain',
-                        position: 'absolute',
-                        left: '50%',
-                        top: '50%',
-                        transform: 'translate(-50%, -50%)'
-                    });
+                    c.style.width = cw + 'px';
+                    c.style.height = ch + 'px';
+                    c.style.maxWidth = '100%';
+                    c.style.maxHeight = '100%';
                     this._canvas = c;
                     this._ctx = c.getContext('2d');
                     this._ctx.scale(dpr, dpr);