feat(chat/notif): single hover action-pill; sender DP in desktop+mobile notifications

- Message actions (reply/react/edit/delete) consolidated into ONE hover pill anchored to the
  bubble's top-right, overlapping it so on short messages the icons no longer float off into
  empty space and vanish before you can click.
- Desktop toast + mobile(FCM)/web-background push now show the sender's real DP:
  * renderer passes the DP URL through; desktop shell downloads it for the toast icon
    (canvas-drawing an external DP tainted it → initials). Desktop bumped to 0.1.4.
  * DM push payload carries icon=sender avatar; sw.js already uses it (web background),
    sendFcm sets notification.image (Android).

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

server/push.js

@@ -53,7 +53,9 @@ async function fcmAccessToken() {
 }
 async function sendFcm(token, payload) {
   const at = await fcmAccessToken();
-  const msg = { message: { token, notification: { title: payload.title || 'Biz Connect', body: payload.body || '' }, data: strData(payload.data || {}) } };
+  const notif = { title: payload.title || 'Biz Connect', body: payload.body || '' };
+  if (payload.icon) notif.image = payload.icon; // sender/group DP shown by Android
+  const msg = { message: { token, notification: notif, data: strData(payload.data || {}) } };
   const res = await fetch('https://fcm.googleapis.com/v1/projects/' + fcmSA.project_id + '/messages:send', {
     method: 'POST', headers: { Authorization: 'Bearer ' + at, 'Content-Type': 'application/json' }, body: JSON.stringify(msg),
   });