feat(override-editor): add shield duration override support

1. add shield_duration translation and override config entry
2. add warning tip for shield duration setting with usage notes
3. control tip visibility based on whether shield_duration is configured

put/web/src/constants.js

@@ -161,6 +161,8 @@ export const OVERRIDE_KEYS = [
   { key: 'para', label: 'para 麻痹概率' },
   { key: 'bck', label: 'bck 击退' },
   { key: 'bck_chance', label: 'bck_chance 击退概率' },
+  // 护盾型覆写：仅 kind=Shield 技能生效（底座 6301 默认 7 秒）
+  { key: 'shield_duration', label: 'shield_duration 护盾持续秒(0=永久)' },
   // buff 型覆写：值为 BuffList 配置 id，前端用 meta.BuffList 渲染下拉（支持 allow-create 手输兜底）
   // buff 语义为增益，缺省挂施法者自身；debuff 语义为对敌减益，缺省挂被命中者（目标不可覆写）
   { key: 'timed_buff_id', label: 'timed_buff_id 计时buff', type: 'buff' },