重构: 前端架构审查降技术债·i18n收口(高ROI)

- 新建 src/i18n/i18n-helpers.ts: 类型安全 t + currentLocale(any中转内部1处带注释)
- 12文件改 i18n as any 样板收口: utils/time + stores(knowledge/project/{ideas,projects,tasks,workflow}) + composables(aiShared/useAiConversations/useAiEvents/useAiSend/useAiStream/useToolCard)
- as any 22→10(i18n 13→0对外), 签名统一(key, named?)
- useToolCard文档块同步(防AI被过时注释误导)

src/stores/knowledge.ts

@@ -1,6 +1,6 @@
 import { reactive, computed } from 'vue'
 import { knowledgeApi } from '@/api'
-import i18n from '@/i18n'
+import { t } from '@/i18n/i18n-helpers'
 import type {
   KnowledgeRecord,
   KnowledgeDetailPayload,
@@ -10,9 +10,6 @@ import type {
   KnowledgeConfig,
 } from '@/api/types'
 
-// composable 外全局 i18n 实例(非 setup 上下文)
-const t = ((i18n as any).global.t as (k: string) => string).bind((i18n as any).global)
-
 // ── 全局响应式状态（单例） ──
 
 const state = reactive({