Fix tags display in PostDetailModal

- Use event_tags (API field) instead of tags
- Add impact-based coloring (green positive, red negative, default neutral)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/Posts/PostDetailModal.jsx

@@ -1001,13 +1001,19 @@ export default function PostDetailModal({ post, onClose, onPostUpdated, onPostDe
               )}
 
               {/* Tags */}
-              {post?.tags?.length > 0 && (
+              {(post?.event_tags?.length > 0 || post?.tags?.length > 0) && (
                 <div className="flex flex-wrap gap-2 mb-4">
-                  {post.tags.slice(0, 6).map((tag, i) => (
-                    <span key={i} className="px-3 py-1.5 rounded-full bg-themed-accent text-accent text-xs font-medium">
+                  {(post.event_tags || post.tags).slice(0, 6).map((tag, i) => {
+                    const impact = post?.topic_impacts?.[tag] ?? 0;
+                    const colorClass = impact > 0 ? "bg-green-500/20 text-green-400" :
+                                       impact < 0 ? "bg-red-500/20 text-red-400" :
+                                       "bg-themed-accent text-accent";
+                    return (
+                      <span key={i} className={`px-3 py-1.5 rounded-full text-xs font-medium ${colorClass}`}>
                         #{tag}
                       </span>
-                  ))}
+                    );
+                  })}
                 </div>
               )}