fix: 태그를 nullable로 변경

Author: jayychoi

src/components/blog/post-card.tsx

@@ -10,7 +10,7 @@ interface PostCardProps {
   description?: string;
   created: string;
   category: string;
-  tags: string[];
+  tags?: string[];
   series?: string;
   order?: number;
 }

src/components/blog/post-meta-badges.tsx

@@ -2,7 +2,7 @@ import { CategoryBadge, SeriesBadge, TagBadge } from "./badges";
 
 interface PostMetaBadgesProps {
   category: string;
-  tags: string[];
+  tags?: string[];
   series?: string;
   order?: number;
   seriesCount?: number;
@@ -28,7 +28,7 @@ export default function PostMetaBadges({
           className={linkClassName}
         />
       )}
-      {tags.map((tag) => (
+      {tags?.map((tag) => (
         <TagBadge key={tag} tag={tag} className={linkClassName} />
       ))}
     </>

src/lib/posts.ts

@@ -19,7 +19,7 @@ export function getPostsByCategory(category: string): Post[] {
 
 // 태그 필터
 export function getPostsByTag(tag: string): Post[] {
-  return getAllPosts().filter((p) => p.tags.includes(tag));
+  return getAllPosts().filter((p) => p.tags?.includes(tag));
 }
 
 // 시리즈 필터 (order 순 정렬)
@@ -54,7 +54,7 @@ export function getAllCategories(): { name: string; count: number }[] {
 export function getAllTags(): { name: string; count: number }[] {
   const map = new Map<string, number>();
   for (const p of posts) {
-    for (const tag of p.tags) {
+    for (const tag of p.tags ?? []) {
       map.set(tag, (map.get(tag) ?? 0) + 1);
     }
   }

src/lib/search.ts

@@ -6,7 +6,7 @@ export interface SearchItem {
   title: string;
   description: string;
   category: string;
-  tags: string[];
+  tags?: string[];
   content: string;
 }