Persist feed tab across navigation — back button returns to correct tab

Feed tab (Global/Following) moved from local state to UI store so it
survives thread/profile navigation. Fixed hardcoded "feed" in openThread
calls to pass currentView instead.

src/components/feed/Feed.tsx

@@ -2,19 +2,17 @@ import { useEffect, useState } from "react";
 import { useFeedStore } from "../../stores/feed";
 import { useUserStore } from "../../stores/user";
 import { useMuteStore } from "../../stores/mute";
+import { useUIStore } from "../../stores/ui";
 import { fetchFollowFeed, getNDK } from "../../lib/nostr";
 import { NoteCard } from "./NoteCard";
 import { ComposeBox } from "./ComposeBox";
 import { NDKEvent } from "@nostr-dev-kit/ndk";
 
-type FeedTab = "global" | "following";
-
 export function Feed() {
   const { notes, loading, connected, error, connect, loadCachedFeed, loadFeed, focusedNoteIndex } = useFeedStore();
   const { loggedIn, follows } = useUserStore();
   const { mutedPubkeys } = useMuteStore();
-
-  const [tab, setTab] = useState<FeedTab>("global");
+  const { feedTab: tab, setFeedTab: setTab } = useUIStore();
   const [followNotes, setFollowNotes] = useState<NDKEvent[]>([]);
   const [followLoading, setFollowLoading] = useState(false);
 

src/components/feed/NoteCard.tsx

@@ -191,7 +191,7 @@ export function NoteCard({ event, focused }: NoteCardProps) {
                 onClick={async (e) => {
                   e.stopPropagation();
                   const parent = await fetchNoteById(parentEventId);
-                  if (parent) openThread(parent, "feed");
+                  if (parent) openThread(parent, currentView as "feed" | "profile");
                 }}
                 className="hover:text-accent transition-colors"
               >

src/components/feed/NoteContent.tsx

@@ -173,7 +173,7 @@ function tryOpenNostrEntity(raw: string): boolean {
 
 function QuotePreview({ eventId }: { eventId: string }) {
   const [event, setEvent] = useState<NDKEvent | null>(null);
-  const { openThread } = useUIStore();
+  const { openThread, currentView } = useUIStore();
   const profile = useProfile(event?.pubkey ?? "");
 
   useEffect(() => {
@@ -189,7 +189,7 @@ function QuotePreview({ eventId }: { eventId: string }) {
   return (
     <div
       className="mt-2 border border-border bg-bg-raised px-3 py-2 cursor-pointer hover:bg-bg-hover transition-colors"
-      onClick={(e) => { e.stopPropagation(); openThread(event, "feed"); }}
+      onClick={(e) => { e.stopPropagation(); openThread(event, currentView as "feed" | "profile"); }}
     >
       <div className="flex items-center gap-2 mb-1">
         {profile?.picture && (