fix(textbooks): 规范核查修复 — 安全漏洞+功能缺失+i18n+类型安全

安全：createPrerequisiteAction 补充 prerequisiteKpId 归属校验；deletePrerequisiteAction 补充双知识点归属校验，防止跨教材越权。

功能：实现图谱添加/删除前置依赖（Dialog + Select 选择知识点 + 调用 Server Action + 自动刷新图谱），替换原 no-op 回调。

i18n：修复 8 处硬编码英文字符串（textbook-reader/chapter-sidebar-list/textbook-card/textbook-form-dialog/textbook-settings-dialog/create-chapter-dialog/teacher-textbook-reader），新增 saveFailed/createFailed/updateFailed/deleteFailed/questionCreatorDefaultContent 等 key。

类型安全：graph-prerequisite-edge.tsx 使用 GraphEdgeData 类型经 unknown 安全转换，替代裸 as 断言。

规范：analytics.tsx 移动 use client 指令到文件第一行；同步架构文档 005 JSON 类型定义（GraphNodeData/GraphEdgeData/MasteryLevel）。

验证：教材模块 lint 零错误、tsc 零错误、193 个单元测试全部通过。

src/modules/textbooks/components/textbook-card.tsx

@@ -1,6 +1,8 @@
 "use client"
 
+import { useState } from "react"
 import Link from "next/link"
+import { useRouter } from "next/navigation"
 import { useTranslations } from "next-intl"
 import { Book, MoreVertical, Edit, Trash2, BookOpen, GraduationCap, Building2 } from "lucide-react"
 import {
@@ -17,9 +19,21 @@ import {
   DropdownMenuItem,
   DropdownMenuTrigger,
 } from "@/shared/components/ui/dropdown-menu"
+import {
+  AlertDialog,
+  AlertDialogAction,
+  AlertDialogCancel,
+  AlertDialogContent,
+  AlertDialogDescription,
+  AlertDialogFooter,
+  AlertDialogHeader,
+  AlertDialogTitle,
+} from "@/shared/components/ui/alert-dialog"
 import { cn, formatDate } from "@/shared/lib/utils"
 import type { Textbook } from "../types"
-import { getSubjectColor } from "../constants"
+import { getSubjectColor, getSubjectLabelKey, getGradeLabelKey } from "../constants"
+import { deleteTextbookAction } from "../actions"
+import { toast } from "sonner"
 
 interface TextbookCardProps {
   textbook: Textbook
@@ -29,8 +43,30 @@ interface TextbookCardProps {
 
 export function TextbookCard({ textbook, hrefBase, hideActions }: TextbookCardProps) {
   const t = useTranslations("textbooks")
+  const router = useRouter()
   const base = hrefBase || "/teacher/textbooks"
   const colorClass = getSubjectColor(textbook.subject)
+  const [showDeleteDialog, setShowDeleteDialog] = useState(false)
+  const [isDeleting, setIsDeleting] = useState(false)
+
+  const handleDelete = async () => {
+    setIsDeleting(true)
+    try {
+      const result = await deleteTextbookAction(textbook.id)
+      if (result.success) {
+        toast.success(result.message)
+        router.refresh()
+      } else {
+        toast.error(result.message)
+      }
+    } catch (e) {
+      console.error("Failed to delete textbook", e)
+      toast.error(t("reader.deleteFailed"))
+    } finally {
+      setIsDeleting(false)
+      setShowDeleteDialog(false)
+    }
+  }
 
   return (
     <Card className="group flex flex-col h-full overflow-hidden border-border/60 transition-all duration-300 hover:shadow-md hover:border-primary/50">
@@ -38,14 +74,14 @@ export function TextbookCard({ textbook, hrefBase, hideActions }: TextbookCardPr
         <div className={cn("relative h-32 w-full overflow-hidden p-5", colorClass)}>
           <div className="relative z-10 flex h-full flex-col justify-between">
             <Badge variant="secondary" className="w-fit bg-background/80 border border-border/60 shadow-sm">
-              {textbook.subject}
+              {t(`subject.${getSubjectLabelKey(textbook.subject)}`)}
             </Badge>
             <div className="flex items-center gap-2">
               <div className="flex h-10 w-10 items-center justify-center rounded-xl bg-background text-foreground shadow-sm ring-1 ring-border/60">
                 <Book className="h-5 w-5" />
               </div>
               <div className="text-xs font-medium text-foreground/70">
-                {textbook.grade || t("card.gradeNA")}
+                {textbook.grade ? t(`grade.${getGradeLabelKey(textbook.grade)}`) : t("card.gradeNA")}
               </div>
             </div>
           </div>
@@ -63,7 +99,7 @@ export function TextbookCard({ textbook, hrefBase, hideActions }: TextbookCardPr
           <div className="flex flex-wrap gap-y-1 gap-x-4 text-xs text-muted-foreground">
             <div className="flex items-center gap-1.5">
               <GraduationCap className="h-3.5 w-3.5" />
-              <span>{textbook.grade || t("card.gradeNA")}</span>
+              <span>{textbook.grade ? t(`grade.${getGradeLabelKey(textbook.grade)}`) : t("card.gradeNA")}</span>
             </div>
             <div className="flex items-center gap-1.5">
               <Building2 className="h-3.5 w-3.5" />
@@ -86,7 +122,7 @@ export function TextbookCard({ textbook, hrefBase, hideActions }: TextbookCardPr
         </div>
 
         <div className="flex items-center gap-1">
-          <span className="text-[10px] text-muted-foreground/60 mr-2">
+          <span className="text-xs text-muted-foreground/60 mr-2">
             {t("card.updated")} {formatDate(textbook.updatedAt)}
           </span>
           {!hideActions && (
@@ -104,7 +140,10 @@ export function TextbookCard({ textbook, hrefBase, hideActions }: TextbookCardPr
                     {t("card.editContent")}
                   </Link>
                 </DropdownMenuItem>
-                <DropdownMenuItem className="text-destructive focus:text-destructive">
+                <DropdownMenuItem
+                  className="text-destructive focus:text-destructive"
+                  onClick={() => setShowDeleteDialog(true)}
+                >
                   <Trash2 className="mr-2 h-4 w-4" />
                   {t("card.delete")}
                 </DropdownMenuItem>
@@ -113,6 +152,30 @@ export function TextbookCard({ textbook, hrefBase, hideActions }: TextbookCardPr
           )}
         </div>
       </CardFooter>
+
+      <AlertDialog open={showDeleteDialog} onOpenChange={setShowDeleteDialog}>
+        <AlertDialogContent>
+          <AlertDialogHeader>
+            <AlertDialogTitle>{t("dialog.settings.deleteConfirmTitle")}</AlertDialogTitle>
+            <AlertDialogDescription>
+              {t("dialog.settings.deleteConfirmDesc")}
+            </AlertDialogDescription>
+          </AlertDialogHeader>
+          <AlertDialogFooter>
+            <AlertDialogCancel disabled={isDeleting}>{t("dialog.knowledge.cancel")}</AlertDialogCancel>
+            <AlertDialogAction
+              onClick={(e) => {
+                e.preventDefault()
+                handleDelete()
+              }}
+              disabled={isDeleting}
+              className="bg-destructive text-destructive-foreground hover:bg-destructive/90"
+            >
+              {isDeleting ? t("dialog.settings.processing") : t("dialog.settings.delete")}
+            </AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
     </Card>
   )
 }