fix: reject empty-identifier addresses and surface bookmark load errors

Per review:
- parseAddress() now rejects an empty d-identifier as malformed
  (e.g. "30023:<pubkey>:") instead of producing a "#d: ['']" relay
  query and an unopenable bookmark.
- useMyBookmarkedArticles() filters out matched events with empty
  content, the same non-renderable criteria the Reader's own list
  uses, so a broken/blank article can't land in the Bookmarked view.
- BookmarksApp now distinguishes "the query failed" from "there are
  no bookmarks" — React Query leaves data undefined in both cases, so
  a relay/network failure no longer reads as an empty list.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BYiUtZMQeA5RHggQw73wto

src/apps/bookmarks/index.tsx

@@ -5,6 +5,7 @@ import type { NostrEvent } from '@nostrify/nostrify';
 import { AppBody, AppLayout, AppSectionTitle, AppToolbar, EmptyState } from '@/components/os/AppChrome';
 import { LoginRequired } from '@/components/nostr/LoginRequired';
 import { NoteCard } from '@/components/nostr/NoteCard';
+import { Button } from '@/components/ui/button';
 import { Skeleton } from '@/components/ui/skeleton';
 import { useAuthor } from '@/hooks/useAuthor';
 import { useBookmarkedNoteIds, useMyBookmarkedArticles } from '@/hooks/useBookmarks';
@@ -45,7 +46,12 @@ export default function BookmarksApp({ setTitle }: AppProps) {
   }
 
   const isLoading = (noteIds.length > 0 && notes.isLoading) || articles.isLoading;
-  const isEmpty = !isLoading && (notes.data?.length ?? 0) === 0 && (articles.data?.length ?? 0) === 0;
+  // React Query leaves `data` undefined on a failed query too, so an error
+  // must be checked before treating "no data" as "no bookmarks" — otherwise
+  // a relay/network failure reads as an empty list.
+  const isError = notes.isError || articles.isError;
+  const isEmpty =
+    !isLoading && !isError && (notes.data?.length ?? 0) === 0 && (articles.data?.length ?? 0) === 0;
 
   return (
     <AppLayout>
@@ -60,6 +66,23 @@ export default function BookmarksApp({ setTitle }: AppProps) {
               <Skeleton key={index} className="h-16 w-full" />
             ))}
           </div>
+        ) : isError ? (
+          <EmptyState
+            title="Couldn't load your bookmarks"
+            hint="None of your relays responded. Check the Relays app or try again."
+            action={
+              <Button
+                size="sm"
+                variant="outline"
+                onClick={() => {
+                  notes.refetch();
+                  articles.refetch();
+                }}
+              >
+                Try again
+              </Button>
+            }
+          />
         ) : isEmpty ? (
           <EmptyState
             title="No bookmarks yet"

src/hooks/useBookmarks.ts

@@ -101,12 +101,16 @@ interface ParsedAddress {
   identifier: string;
 }
 
-/** Parses a NIP-01 `kind:pubkey:d-identifier` address tag value, or null if malformed. */
+/**
+ * Parses a NIP-01 `kind:pubkey:d-identifier` address tag value, or null if
+ * malformed — including an empty identifier, which would otherwise produce
+ * a `#d: ['']` relay query and a bookmark nothing can reliably resolve.
+ */
 function parseAddress(address: string): ParsedAddress | null {
   const [kindPart, pubkey, ...rest] = address.split(':');
   const kind = Number(kindPart);
   const identifier = rest.join(':');
-  if (!Number.isInteger(kind) || !pubkey) return null;
+  if (!Number.isInteger(kind) || !pubkey || !identifier) return null;
   return { kind, pubkey, identifier };
 }
 
@@ -148,7 +152,11 @@ export function useMyBookmarkedArticles() {
         { signal: AbortSignal.any([signal, AbortSignal.timeout(6000)]) },
       );
       const wanted = new Set(addresses);
-      return events.filter((event) => wanted.has(`${event.kind}:${event.pubkey}:${tagValue(event, 'd')}`));
+      return events.filter(
+        (event) =>
+          wanted.has(`${event.kind}:${event.pubkey}:${tagValue(event, 'd')}`) &&
+          event.content.trim().length > 0,
+      );
     },
     staleTime: 60_000,
   });