fix: guard against double-publish and dropped relay params

Per review:
- handlePublish now also checks publish.isPending itself, not just
  the button's disabled state — a second click landing before React
  re-renders could otherwise fire mutateAsync twice.
- Publishing a draft now merges into the existing params instead of
  replacing them outright, so relay hints (or anything else already
  in params) survive the id being added.

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

src/apps/notes/Draft.tsx

@@ -27,7 +27,10 @@ export function DraftNote({ onPublished }: { onPublished: (id: string) => void }
   const trimmed = draft.trim();
 
   const handlePublish = async () => {
-    if (!trimmed) return;
+    // Guarded here too, not just via the button's `disabled` — React hasn't
+    // necessarily re-rendered with publish.isPending yet when a second click
+    // lands in the same tick, and mutateAsync itself doesn't dedupe calls.
+    if (!trimmed || publish.isPending) return;
     try {
       const event = await publish.mutateAsync({ kind: 1, content: trimmed, tags: [] });
       setDraft('');

src/apps/notes/index.tsx

@@ -67,7 +67,7 @@ export default function NotesApp({ params, setTitle, setParams }: AppProps) {
   }, [id, name, setTitle]);
 
   if (!id) {
-    return <DraftNote onPublished={(publishedId) => setParams({ id: publishedId })} />;
+    return <DraftNote onPublished={(publishedId) => setParams({ ...params, id: publishedId })} />;
   }
 
   if (note.isLoading) {