fix: align text annotations in captures

internal/application/annotation_test.go

@@ -93,3 +93,50 @@ func TestApplyAnnotationsDrawsTextIntoPNG(t *testing.T) {
 		t.Fatalf("expected red text pixels near annotation point")
 	}
 }
+
+func TestApplyAnnotationsWithScaleDrawsTextAtDevicePosition(t *testing.T) {
+	src := image.NewRGBA(image.Rect(0, 0, 220, 120))
+	draw.Draw(src, src.Bounds(), &image.Uniform{C: color.White}, image.Point{}, draw.Src)
+
+	var buf bytes.Buffer
+	if err := png.Encode(&buf, src); err != nil {
+		t.Fatalf("encode source: %v", err)
+	}
+
+	out, err := ApplyAnnotationsWithScale(buf.Bytes(), []Annotation{
+		{
+			Tool:     "text",
+			Color:    "#ef4444",
+			Points:   []Point{{X: 50, Y: 20}},
+			Text:     "T",
+			FontSize: 20,
+		},
+	}, 2, 2)
+	if err != nil {
+		t.Fatalf("apply annotations: %v", err)
+	}
+
+	img, err := png.Decode(bytes.NewReader(out))
+	if err != nil {
+		t.Fatalf("decode output: %v", err)
+	}
+	minX := 999
+	found := false
+	for y := 0; y < img.Bounds().Dy(); y++ {
+		for x := 0; x < img.Bounds().Dx(); x++ {
+			got := color.RGBAModel.Convert(img.At(x, y)).(color.RGBA)
+			if got.R > 180 && got.G < 180 && got.B < 180 {
+				found = true
+				if x < minX {
+					minX = x
+				}
+			}
+		}
+	}
+	if !found {
+		t.Fatalf("expected red text pixels")
+	}
+	if minX < 90 {
+		t.Fatalf("expected text to be drawn near scaled x=100, min red x=%d", minX)
+	}
+}