fix: editable decrypt + windows realtime wake (v0.7.1)

Edit message decrypt:
- handleUpdate in useConversationMessages now refetches the canonical row
  via REST after a realtime UPDATE instead of trusting the realtime
  payload's bytea encoding. Same pattern as handleInsert — base64 vs
  `\x…` hex serialisation varies across supabase/postgrest versions and
  was silently producing undecryptable ciphertext for edited messages
  on the receiver side

Windows WebView2 background throttling:
- ConversationsContext, useFriendships and useConversationMessages now
  listen for visibilitychange / focus / online events and trigger both a
  fresh REST refresh and a best-effort channel.subscribe() on wake.
  WebView2 aggressively throttles background WebSockets and was dropping
  realtime events entirely while the window was minimised, so new
  messages and friend acceptances only surfaced after a manual reload

Bump tauri version 0.7.0 -> 0.7.1

apps/desktop/src/context/ConversationsContext.tsx

@@ -213,7 +213,31 @@ export function ConversationsProvider({ children }: { children: ReactNode }) {
       )
       .subscribe();
 
+    // Windows WebView2 aggressively throttles background WebSockets and
+    // sometimes drops events entirely while the window is minimised. Force a
+    // refresh + realtime reconnect on visibility/focus regain so we never
+    // leave stale conversation lists on a Windows client after the user
+    // returns to the app.
+    const onAwake = () => {
+      if (document.visibilityState !== 'visible') return;
+      void refresh();
+      try {
+        // If the socket got wedged during background throttle, a no-op
+        // unsubscribe+resubscribe brings it back. `subscribe()` on an already
+        // joined channel is a no-op so this is safe.
+        channel.subscribe();
+      } catch {
+        /* ignore — already live */
+      }
+    };
+    document.addEventListener('visibilitychange', onAwake);
+    window.addEventListener('focus', onAwake);
+    window.addEventListener('online', onAwake);
+
     return () => {
+      document.removeEventListener('visibilitychange', onAwake);
+      window.removeEventListener('focus', onAwake);
+      window.removeEventListener('online', onAwake);
       void supabase.removeChannel(channel);
     };
   }, [myId, refresh, markRead]);