feat: 完善时标与天象几何计算并扩展输出接口

- 新增时标、ΔT 模型、质心时间与 UT1 支持
- 改进日月食、月掩、行星事件及路径边界计算
- 完善恒星三维自行与动态距离传播
- 扩展 SVG、GeoJSON、KML 输出与底层距离换算工具
- 整理中英文手册、示例资源及回归测试

jupiter/satellites_test.go

@@ -106,7 +106,7 @@ func TestGalileanSatellitesUseTTFrame(t *testing.T) {
 		time.Date(2026, 4, 2, 18, 0, 0, 0, time.UTC),
 	}
 	for _, date := range dates {
-		want := basic.JupiterGalileanSatelliteObservations(basic.TD2UT(basic.Date2JDE(date.UTC()), true))
+		want := basic.JupiterGalileanSatelliteObservations(basic.UTC2TT(basic.Date2JD(date.UTC())))
 		got := Satellites(date)
 		positions := []GalileanSatellitePosition{got.Io, got.Europa, got.Ganymede, got.Callisto}
 		for i, position := range positions {