feat: wallpaper cropper sdf shader rectangle, better confirmation controls + hide passive tray icons

assets/shaders/crop_sdf.frag

@@ -0,0 +1,40 @@
+#version 440
+layout(location = 0) in vec2 qt_TexCoord0;
+layout(location = 0) out vec4 fragColor;
+
+
+layout(std140, binding = 0) uniform buf {
+    mat4 qt_Matrix;
+    float qt_Opacity;
+    vec2 itemSize;
+    vec4 cropBox;
+    vec4 borderColor;
+    float cornerRadius;
+    float borderWidth;
+    float pixelScale;
+};
+
+float sdRoundBox(vec2 p, vec2 halfSize, float r) {
+	vec2 q = abs(p) - halfSize + r;
+	return length(max(q, 0.0)) + min(max(q.x, q.y), 0.0) - r;
+}
+
+void main() {
+    vec2 sz = itemSize * pixelScale;
+    vec2 p = qt_TexCoord0 * sz;
+    vec4 box = cropBox * pixelScale;
+    float r = cornerRadius * pixelScale;
+    float bw = borderWidth * pixelScale;
+
+    float dImage = sdRoundBox(p - sz * 0.5, sz * 0.5, r);
+    float dCrop  = sdRoundBox(p - (box.xy + box.zw * 0.5), box.zw * 0.5, 0.0);
+
+    float d = max(dImage, dCrop);
+
+    // ramp is exactly 1 physical pixel wide
+    float outer = clamp(0.5 - d, 0.0, 1.0);
+    float inner = clamp(0.5 - (d + bw), 0.0, 1.0);
+    float a = outer - inner;
+
+    fragColor = vec4(borderColor.rgb, 1.0) * (borderColor.a * a * qt_Opacity);
+}