feat(desktop): Phase D — inline-reply notifications (Windows toast reply box)

Reply to a chat straight from the OS notification, no app switch:
- node-notifier (bundles SnoreToast) renders a native Windows toast with a reply box —
  Electron's own Notification can't do Windows inline reply.
- main.js reply-notification handler resolves {text}|{open}|null; preload exposes replyNotify.
- home.html notify() routes chat toasts through it on desktop: a typed reply -> sendReplyTo()
  POSTs to /api/messages without opening the app; a click opens the chat. Web/PWA path unchanged.
- Works only in the installed app (needs the installer's AppUserModelID). desktop 0.1.2, build batch21.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

desktop/preload.js

@@ -19,4 +19,7 @@ contextBridge.exposeInMainWorld('bizConnectNative', Object.freeze({
   // Show the unread-chat count as a badge on the taskbar icon. count=number of chats with
   // unread; dataUrl=a small PNG badge the renderer drew (null to clear).
   setUnread: (count, dataUrl) => ipcRenderer.send('set-unread', { count, dataUrl }),
+  // Native Windows toast with an inline reply box. Resolves to {text} (replied), {open} (clicked)
+  // or null. Lets the user reply to a chat straight from the notification.
+  replyNotify: (payload) => ipcRenderer.invoke('reply-notification', payload),
 }));