Add clone support for scene and automation cards, update sync clock descriptions

- Scene clone: opens capture modal with prefilled name/description/targets
  instead of server-side duplication; removed backend clone endpoint
- Automation clone: opens editor with prefilled conditions, scene, logic,
  deactivation mode (webhook tokens stripped for uniqueness)
- Updated sync clock i18n descriptions to reflect speed-only-on-clock model
- Added entity card clone pattern documentation to server/CLAUDE.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/wled_controller/static/locales/zh.json

@@ -652,6 +652,7 @@
   "automations.created": "自动化已创建",
   "automations.deleted": "自动化已删除",
   "automations.error.name_required": "名称为必填项",
+  "automations.error.clone_failed": "克隆自动化失败",
   "scenes.title": "场景",
   "scenes.add": "捕获场景",
   "scenes.edit": "编辑场景",
@@ -1172,7 +1173,7 @@
   "sync_clock.name.placeholder": "主动画时钟",
   "sync_clock.name.hint": "此同步时钟的描述性名称",
   "sync_clock.speed": "速度：",
-  "sync_clock.speed.hint": "所有关联源共享的速度倍率。1.0 = 正常速度。",
+  "sync_clock.speed.hint": "所有关联源的动画速度倍率。1.0 = 正常，2.0 = 双倍，0.5 = 半速。",
   "sync_clock.description": "描述（可选）：",
   "sync_clock.description.placeholder": "可选描述",
   "sync_clock.description.hint": "关于此时钟用途的可选备注",
@@ -1189,7 +1190,7 @@
   "sync_clock.paused": "时钟已暂停",
   "sync_clock.resumed": "时钟已恢复",
   "sync_clock.reset_done": "时钟已重置为零",
-  "sync_clock.delete.confirm": "删除此同步时钟？使用它的源将恢复为各自的速度。",
+  "sync_clock.delete.confirm": "删除此同步时钟？关联的源将失去同步并以默认速度运行。",
   "color_strip.clock": "同步时钟：",
-  "color_strip.clock.hint": "关联同步时钟以实现同步动画。设置后，速度将来自时钟。"
+  "color_strip.clock.hint": "关联同步时钟以在多个源之间同步动画。速度在时钟上控制。"
 }