Add download button to Zapstore app renderers

Add a download button for the latest release to both the feed and detail
renderers for kind 32267 (Zapstore App Metadata). The feed renderer shows
a compact version button, while the detail renderer shows a prominent
download button in the header. Both fetch the latest release and link to
its file metadata event (kind 1063) for download.

src/components/nostr/kinds/ZapstoreAppDetailRenderer.tsx

@@ -147,6 +147,7 @@ function PlatformItem({ platform }: { platform: Platform }) {
 export function ZapstoreAppDetailRenderer({
   event,
 }: ZapstoreAppDetailRendererProps) {
+  const { addWindow } = useGrimoire();
   const appName = getAppName(event);
   const summary = getAppSummary(event);
   const iconUrl = getAppIcon(event);
@@ -186,6 +187,19 @@ export function ZapstoreAppDetailRenderer({
     });
   }, [releases]);
 
+  // Get the latest release for the header download button
+  const latestRelease = sortedReleases[0] || null;
+  const latestFileEventId = latestRelease
+    ? getReleaseFileEventId(latestRelease)
+    : null;
+  const latestVersion = latestRelease ? getReleaseVersion(latestRelease) : null;
+
+  const handleDownloadLatest = () => {
+    if (latestFileEventId) {
+      addWindow("open", { pointer: { id: latestFileEventId } });
+    }
+  };
+
   return (
     <div className="flex flex-col gap-6 p-6 max-w-4xl mx-auto">
       {/* Header Section */}
@@ -206,7 +220,18 @@ export function ZapstoreAppDetailRenderer({
 
         {/* App Title & Summary */}
         <div className="flex flex-col gap-2 flex-1 min-w-0">
-          <h1 className="text-3xl font-bold">{appName}</h1>
+          <div className="flex items-start justify-between gap-4">
+            <h1 className="text-3xl font-bold">{appName}</h1>
+            {latestFileEventId && (
+              <button
+                onClick={handleDownloadLatest}
+                className="flex items-center gap-2 px-4 py-2 text-sm font-medium text-primary-foreground bg-primary rounded-lg hover:bg-primary/90 transition-colors flex-shrink-0"
+              >
+                <FileDown className="size-4" />
+                {latestVersion ? `Download v${latestVersion}` : "Download"}
+              </button>
+            )}
+          </div>
           {summary && (
             <p className="text-muted-foreground text-base">{summary}</p>
           )}

src/components/nostr/kinds/ZapstoreAppRenderer.tsx

@@ -6,28 +6,92 @@ import {
 import {
   getAppName,
   getAppSummary,
+  getAppIdentifier,
   detectPlatforms,
+  getReleaseVersion,
+  getReleaseFileEventId,
 } from "@/lib/zapstore-helpers";
 import { PlatformIcon } from "./zapstore/PlatformIcon";
+import { use$ } from "applesauce-react/hooks";
+import eventStore from "@/services/event-store";
+import { useMemo } from "react";
+import { useGrimoire } from "@/core/state";
+import { FileDown } from "lucide-react";
 
 /**
  * Renderer for Kind 32267 - App Metadata
- * Clean feed view with app name, summary, and platform icons
+ * Clean feed view with app name, summary, platform icons, and download button
  */
 export function ZapstoreAppRenderer({ event }: BaseEventProps) {
+  const { addWindow } = useGrimoire();
   const appName = getAppName(event);
   const summary = getAppSummary(event);
+  const identifier = getAppIdentifier(event);
   const platforms = detectPlatforms(event);
 
+  // Query for releases that reference this app
+  const releasesFilter = useMemo(() => {
+    if (!identifier) {
+      return { kinds: [30063], ids: [] };
+    }
+    return {
+      kinds: [30063],
+      "#a": [`32267:${event.pubkey}:${identifier}`],
+    };
+  }, [event.pubkey, identifier]);
+
+  const releases = use$(
+    () => eventStore.timeline(releasesFilter),
+    [releasesFilter],
+  );
+
+  // Get the latest release (by version or created_at)
+  const latestRelease = useMemo(() => {
+    if (!releases || releases.length === 0) return null;
+    return [...releases].sort((a, b) => {
+      const versionA = getReleaseVersion(a);
+      const versionB = getReleaseVersion(b);
+      if (versionA && versionB) {
+        return versionB.localeCompare(versionA, undefined, { numeric: true });
+      }
+      return b.created_at - a.created_at;
+    })[0];
+  }, [releases]);
+
+  const latestFileEventId = latestRelease
+    ? getReleaseFileEventId(latestRelease)
+    : null;
+  const latestVersion = latestRelease ? getReleaseVersion(latestRelease) : null;
+
+  const handleDownload = (e: React.MouseEvent) => {
+    e.stopPropagation();
+    if (latestFileEventId) {
+      addWindow("open", { pointer: { id: latestFileEventId } });
+    }
+  };
+
   return (
     <BaseEventContainer event={event}>
       <div className="flex flex-col gap-2">
-        <ClickableEventTitle
-          event={event}
-          className="text-base font-semibold text-foreground"
-        >
-          {appName}
-        </ClickableEventTitle>
+        <div className="flex items-center justify-between gap-2">
+          <ClickableEventTitle
+            event={event}
+            className="text-base font-semibold text-foreground"
+          >
+            {appName}
+          </ClickableEventTitle>
+
+          {latestFileEventId && (
+            <button
+              onClick={handleDownload}
+              className="flex items-center gap-1.5 px-2 py-1 text-xs font-medium text-primary border border-primary/20 rounded hover:bg-primary/10 transition-colors flex-shrink-0"
+              title={latestVersion ? `Download v${latestVersion}` : "Download"}
+            >
+              <FileDown className="size-3" />
+              {latestVersion ? `v${latestVersion}` : "Download"}
+            </button>
+          )}
+        </div>
 
         {summary && (
           <p className="text-sm text-muted-foreground line-clamp-2">