feat: 完善日月食与月掩几何链路并扩展历法接口

- 新增日月食中心带、偏食带、阴影足迹、等时线、食分线及升落边界计算，支持极区与混合食拓扑
- 新增日食单时刻阴影求解器、站心状态查询、批量采样和 ΔT 覆盖接口
- 重构恒星与行星月掩路径，补充有限盘面接触、站心修正、掩带宽度、极区投影及升落边界
- 扩展 SVG 与 GeoJSON 输出，支持详细面板、全球/极区/地球投影、边界闭合、时间标记和拓扑签名
- 扩展日月食候选搜索、局地搜索、沙罗序列预计算与范围外推，补充系列锚点和成员一致性校验
- 补齐古历纪年、儒略历独有闰日、多公历候选、历法改革跨日及精确日期运算接口
- 优化 ΔT、章动、恒星时、月球地平线、事件根搜索和本地星历缓存，降低重复计算开销并提升边界稳定

lite/moon/moon.go

@@ -60,27 +60,34 @@ func ApparentRaDec(date time.Time, lon, lat float64) (float64, float64) {
 	return state.RightAscension, state.Declination
 }
 
+func topocentricHorizontal(date time.Time, lon, lat float64) (altitude, azimuth, hourAngle float64) {
+	jd := basic.Date2JDE(date.UTC())
+	state := lite.MoonTopocentric(jd, lon, lat, 0)
+	return lite.HorizontalCoordinates(state.RightAscension, state.Declination, jd, lon, lat)
+}
+
 // HourAngle 轻量时角 / lightweight hour angle.
 func HourAngle(date time.Time, lon, lat float64) float64 {
-	_, _, hourAngle := lite.HorizontalCoordinates(ApparentRa(date, lon, lat), ApparentDec(date, lon, lat), basic.Date2JDE(date.UTC()), lon, lat)
+	_, _, hourAngle := topocentricHorizontal(date, lon, lat)
 	return hourAngle
 }
 
 // Azimuth 轻量方位角 / lightweight azimuth.
 func Azimuth(date time.Time, lon, lat float64) float64 {
-	_, azimuth, _ := lite.HorizontalCoordinates(ApparentRa(date, lon, lat), ApparentDec(date, lon, lat), basic.Date2JDE(date.UTC()), lon, lat)
+	_, azimuth, _ := topocentricHorizontal(date, lon, lat)
 	return azimuth
 }
 
 // Altitude 轻量高度角 / lightweight altitude.
 func Altitude(date time.Time, lon, lat float64) float64 {
-	altitude, _, _ := lite.HorizontalCoordinates(ApparentRa(date, lon, lat), ApparentDec(date, lon, lat), basic.Date2JDE(date.UTC()), lon, lat)
+	altitude, _, _ := topocentricHorizontal(date, lon, lat)
 	return altitude
 }
 
 // Zenith 轻量天顶距 / lightweight zenith distance.
 func Zenith(date time.Time, lon, lat float64) float64 {
-	return 90 - Altitude(date, lon, lat)
+	altitude, _, _ := topocentricHorizontal(date, lon, lat)
+	return 90 - altitude
 }
 
 // SunMoonLoDiff 轻量日月黄经差 / lightweight Moon-Sun ecliptic-longitude difference.