feat: Add new emoji assets and an UpdateBanner component.

packages/platform-web/src/index.js

@@ -0,0 +1,41 @@
+/**
+ * Web/Capacitor platform implementation.
+ * Uses Web Crypto API, localStorage, and Page Visibility API.
+ */
+import crypto from './crypto.js';
+import session from './session.js';
+import settings from './settings.js';
+import idle from './idle.js';
+
+const webPlatform = {
+  crypto,
+  session,
+  settings,
+  idle,
+  links: {
+    openExternal(url) {
+      window.open(url, '_blank', 'noopener,noreferrer');
+    },
+    async fetchMetadata(url) {
+      // On web, metadata fetching would hit CORS. Use a Convex action or proxy instead.
+      // Return null to gracefully skip link previews that require server-side fetching.
+      return null;
+    },
+  },
+  screenCapture: {
+    async getScreenSources() {
+      // Web uses getDisplayMedia directly (no source picker like Electron).
+      // Return empty array; the web UI should call navigator.mediaDevices.getDisplayMedia() directly.
+      return [];
+    },
+  },
+  windowControls: null,
+  updates: null,
+  features: {
+    hasWindowControls: false,
+    hasScreenCapture: true,
+    hasNativeUpdates: false,
+  },
+};
+
+export default webPlatform;