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

moon/occultation_star_test.go

@@ -149,13 +149,13 @@ func TestFindStarOccultationsReturnsCompleteContactsOutsideQueryWindow(t *testin
 }
 
 func occultationTestTimeToTT(value time.Time) float64 {
-	return basic.TD2UT(basic.Date2JDE(value.UTC()), true)
+	return basic.UTC2TT(basic.Date2JD(value.UTC()))
 }
 
 func occultationTestMoonTopocentricRaDec(tt float64, observer Observer, n int) (float64, float64) {
 	ra, dec := basic.HMoonGeocentricApparentRaDecN(tt, n)
 	distanceAU := basic.HMoonAwayN(tt, n) / 149597870.7
-	ra, dec = basic.TopocentricRaDec(ra, dec, observer.Latitude, observer.Longitude, basic.TD2UT(tt, false), distanceAU, observer.Height)
+	ra, dec = basic.TopocentricRaDec(ra, dec, observer.Latitude, observer.Longitude, basic.TT2UTC(tt), distanceAU, observer.Height)
 	ra = math.Mod(ra, 360)
 	if ra < 0 {
 		ra += 360