Remove unused useReactionCount, seed reactions from batch engagement

- Delete useReactionCount hook (replaced by useReactions)
- Remove fetchReactionCount (no longer referenced)
- Seed per-note reaction cache from fetchBatchEngagement in trending
  feed, so emoji pills render instantly without individual fetches

src/hooks/useReactionCount.ts

@@ -1,29 +0,0 @@
-import { useEffect, useState } from "react";
-import { fetchReactionCount } from "../lib/nostr";
-
-const cache = new Map<string, number>();
-
-export function useReactionCount(eventId: string): [number | null, (delta: number) => void] {
-  const [count, setCount] = useState<number | null>(() => cache.get(eventId) ?? null);
-
-  useEffect(() => {
-    if (cache.has(eventId)) {
-      setCount(cache.get(eventId)!);
-      return;
-    }
-    fetchReactionCount(eventId).then((n) => {
-      cache.set(eventId, n);
-      setCount(n);
-    });
-  }, [eventId]);
-
-  const adjust = (delta: number) => {
-    setCount((prev) => {
-      const next = (prev ?? 0) + delta;
-      cache.set(eventId, next);
-      return next;
-    });
-  };
-
-  return [count, adjust];
-}

src/lib/nostr/engagement.ts

@@ -15,12 +15,6 @@ export async function publishReaction(eventId: string, eventPubkey: string, reac
   await event.publish();
 }
 
-export async function fetchReactionCount(eventId: string): Promise<number> {
-  const instance = getNDK();
-  const filter: NDKFilter = { kinds: [NDKKind.Reaction], "#e": [eventId] };
-  const events = await fetchWithTimeout(instance, filter, SINGLE_TIMEOUT);
-  return events.size;
-}
 
 export interface GroupedReactions {
   groups: Map<string, number>;

src/lib/nostr/index.ts

@@ -2,7 +2,7 @@ export { getNDK, getNDKUptimeMs, connectToRelays, ensureConnected, resetNDK, get
 export { fetchGlobalFeed, fetchFollowFeed, fetchUserNotes, fetchUserNotesNIP65, fetchNoteById, fetchReplies, publishNote, publishReply, publishRepost, publishQuote, fetchHashtagFeed, fetchThreadEvents, fetchAncestors } from "./notes";
 export { publishProfile, publishContactList, fetchProfile, fetchFollowSuggestions, fetchMentions, fetchFollowers, fetchNewFollowers } from "./social";
 export { publishArticle, fetchArticle, fetchAuthorArticles, fetchArticleFeed, searchArticles, fetchByAddr } from "./articles";
-export { publishReaction, fetchReactionCount, fetchReplyCount, fetchZapCount, fetchReactions, groupReactions, fetchBatchEngagement, fetchZapsReceived, fetchZapsSent } from "./engagement";
+export { publishReaction, fetchReplyCount, fetchZapCount, fetchReactions, groupReactions, fetchBatchEngagement, fetchZapsReceived, fetchZapsSent } from "./engagement";
 export type { GroupedReactions, BatchEngagement } from "./engagement";
 export { fetchDMConversations, fetchDMThread, sendDM, decryptDM } from "./dms";
 export { fetchBookmarkList, publishBookmarkList, fetchBookmarkListFull, publishBookmarkListFull } from "./bookmarks";

src/stores/feed.ts

@@ -1,6 +1,7 @@
 import { create } from "zustand";
 import { NDKEvent, NDKFilter, NDKKind, NDKSubscription, NDKSubscriptionCacheUsage } from "@nostr-dev-kit/ndk";
 import { connectToRelays, ensureConnected, resetNDK, fetchGlobalFeed, fetchBatchEngagement, fetchTrendingCandidates, getNDK } from "../lib/nostr";
+import { seedReactionsCache } from "../hooks/useReactions";
 import { useToastStore } from "./toast";
 import { dbLoadFeed, dbSaveNotes } from "../lib/db";
 import { diagWrapFetch, logDiag, startRelaySnapshots, getRelayStates } from "../lib/feedDiagnostics";
@@ -232,6 +233,13 @@ export const useFeedStore = create<FeedState>((set, get) => ({
       const eventIds = notes.map((n) => n.id).filter(Boolean) as string[];
       const engagement = await fetchBatchEngagement(eventIds);
 
+      // Seed per-note reaction cache so emoji pills render instantly
+      for (const [id, eng] of engagement) {
+        if (eng.reactionGroups.size > 0) {
+          seedReactionsCache(id, eng.reactionGroups, eng.myReactions);
+        }
+      }
+
       const now = Math.floor(Date.now() / 1000);
       const scored = notes
         .map((note) => {