feat: 引入可切换星历模型并扩展天象观测链路

- 新增半解析、旧模型、自定义与多源堆叠星历实例，提供 Context、Instance、SPK 读取及状态与视位置计算
- 统一太阳、月球和行星实例接口，扩展黄经穿越、留、相位、最近角距、偕日可见、任意高度升落、轨道节点及凌日等天象查询
- 完善日月食、月掩与凌日的月缘剖面、有限盘面接触、站心修正、局地可见性、全球路径和地图输出
- 新增 SVG、GeoJSON、KML 天象输出及凌日、月掩和月缘地形相关缓存与几何求解
- 新增恒星星表导入与查询，支持 CSV、Hipparcos、BSC5、Stellarium 等格式及名称、交叉标识、锥面检索和星等过滤
- 补充 IAU 2006、地球定向、折射消光、大气观测、轨道传播及半解析行星/月球数据支持
- 将默认未来民用时标切换为 TimeScaleLeapHour，更新 2027–2400 农历速查表、中文日期解析和时区边界处理
- 增加事件基线、跨模型回归、几何边界、月缘地形和输出契约测试，完善中英文手册、示例资源、NOTICE 与忽略规则

moon/occultation.go

@@ -41,9 +41,12 @@ const (
 	// OccultationPartial 表示掩甚时有限目标盘面只有部分被覆盖。
 	// OccultationPartial means only part of a finite target disk is covered at greatest occultation.
 	OccultationPartial = basic.OccultationPartial
-	// OccultationGrazing 表示两边缘相切，且没有正持续时间的重叠。
-	// OccultationGrazing means the limbs are tangent without a positive-duration overlap.
+	// OccultationGrazing 表示掠掩：圆月面下两边缘相切；按月缘剖面求解时星迹始终在月缘起伏带内，可有多段遮挡。
+	// OccultationGrazing is a graze: tangent limbs with a circular Moon, or a track inside the limb relief band with a limb profile.
 	OccultationGrazing = basic.OccultationGrazing
+	// OccultationNone 表示月缘剖面下恒星未被遮挡，只出现在精密剖面结果中。
+	// OccultationNone means the star is never hidden by the limb profile; it only appears in precise profile results.
+	OccultationNone = basic.OccultationNone
 )
 
 // OccultationPlanet 标识有限盘面行星目标。
@@ -171,14 +174,12 @@ type StarOccultationInstant = basic.StarOccultationInstant
 // PlanetOccultationInstant contains the visible partial and total planetary footprints at one requested instant.
 type PlanetOccultationInstant = basic.PlanetOccultationInstant
 
-// StarOccultationFootprintAt 计算指定时刻的精确恒星月掩可见足迹。
-// StarOccultationFootprintAt calculates the exact visible stellar-occultation footprint at one instant.
-func StarOccultationFootprintAt(at time.Time, star StarCoordinate) (StarOccultationInstant, error) {
-	return basic.StarOccultationFootprintAt(at, star)
+// StarOccultationFootprintAt 计算指定时刻的精确恒星月掩可见足迹 / exact stellar occultation footprint at an instant.
+func (module *Moon) StarOccultationFootprintAt(at time.Time, star StarCoordinate) (StarOccultationInstant, error) {
+	return basic.StarOccultationFootprintAtWithInstance(at, star, module.inst)
 }
 
-// PlanetOccultationFootprintsAt 计算指定时刻的精确行星偏掩和全掩可见足迹。
-// PlanetOccultationFootprintsAt calculates the exact visible partial and total planetary footprints at one instant.
-func PlanetOccultationFootprintsAt(at time.Time, planet OccultationPlanet) (PlanetOccultationInstant, error) {
-	return basic.PlanetOccultationFootprintsAt(at, planet)
+// PlanetOccultationFootprintsAt 计算指定时刻的精确行星偏掩和全掩可见足迹 / exact planetary occultation footprints at an instant.
+func (module *Moon) PlanetOccultationFootprintsAt(at time.Time, planet OccultationPlanet) (PlanetOccultationInstant, error) {
+	return basic.PlanetOccultationFootprintsAtWithInstance(at, planet, module.inst)
 }