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

basic/solar_eclipse_18741010_regression_test.go

@@ -12,7 +12,7 @@ import (
 // be rebuilt from those samples instead of being exported as the short ribbon.
 func TestSolarEclipse18741010GrazingAnnularBandContainsSweep(t *testing.T) {
 	result := SolarEclipsePartialFootprints(
-		JDECalc(1874, 10, 10),
+		JDCalc(1874, 10, 10),
 		SolarEclipsePartialFootprintOptions{
 			StepDays: 2.0 / 1440.0, BoundaryPoints: 96, RiseSetStepDays: 2.0 / 1440.0,
 		},