feat(backgrounds): add constellation background

src/locales/zh.json

@@ -1045,6 +1045,8 @@
       "matrixRainDesc": "下落的字符列",
       "liquidGradient": "流体渐变",
       "liquidGradientDesc": "模糊的网格渐变色块",
+      "constellation": "星座",
+      "constellationDesc": "由线条连接的粒子",
       "geminiEffect": "Gemini效果",
       "geminiEffectDesc": "类似Google Gemini的SVG效果",
       "speed": "速度",
@@ -1068,6 +1070,7 @@
       "lineColor": "线条颜色",
       "wind": "风力",
       "charset": "字符集",
+      "linkDistance": "连接距离",
       "bgColor": "背景颜色",
       "fillColor": "填充颜色",
       "color1": "颜色1",