fix: message sending fallback + iOS zoom on input + openOrCreatePrivate

- MessageInput: HTTP fallback when WebSocket not OPEN (prevents silent failures)
- WsClient: add trySend() returning bool to detect WS availability
- Backend: POST /api/messages/chat/:chatId endpoint for HTTP message send
- openOrCreatePrivate: use openChat() for consistency after refreshing chat list
- iOS fix: inputs get font-size:16px on mobile to prevent Safari auto-zoom

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/routes/messages.ts

@@ -86,6 +86,55 @@ export default async function messageRoutes(app: FastifyInstance) {
     }));
   });
 
+  // Send text message via HTTP (fallback when WS unavailable)
+  app.post('/chat/:chatId', async (req, reply) => {
+    const { id: userId } = req.user as { id: string };
+    const { chatId } = req.params as { chatId: string };
+    const { content, type = 'text', replyToId } = req.body as any;
+
+    if (!content?.trim()) return reply.status(400).send({ error: 'Empty message' });
+
+    const { rows: [member] } = await pool.query(
+      'SELECT role, can_send_messages FROM chat_members WHERE chat_id = $1 AND user_id = $2',
+      [chatId, userId]
+    );
+    if (!member) return reply.status(403).send({ error: 'Not a member' });
+    if (!member.can_send_messages && member.role === 'member') return reply.status(403).send({ error: 'No permission' });
+
+    const { rows: [chat] } = await pool.query('SELECT type FROM chats WHERE id = $1', [chatId]);
+    if (chat.type === 'channel' && !['owner', 'admin'].includes(member.role)) return reply.status(403).send({ error: 'No permission' });
+
+    const { rows: [msg] } = await pool.query(
+      `INSERT INTO messages (chat_id, sender_id, content, type, reply_to_id)
+       VALUES ($1,$2,$3,$4,$5) RETURNING *`,
+      [chatId, userId, content.trim(), type, replyToId || null]
+    );
+
+    const { rows: [sender] } = await pool.query(
+      'SELECT id, username, display_name, avatar_color FROM users WHERE id = $1', [userId]
+    );
+
+    const fullMsg = {
+      id: msg.id, chatId: msg.chat_id, content: msg.content, type: msg.type,
+      isDeleted: false, isEdited: false, createdAt: msg.created_at,
+      replyTo: null, attachments: [],
+      sender: { id: sender.id, username: sender.username, displayName: sender.display_name, avatarColor: sender.avatar_color }
+    };
+
+    // Broadcast via WS to all members
+    const { connections } = await import('../ws.js');
+    const { rows: members } = await pool.query('SELECT user_id FROM chat_members WHERE chat_id = $1', [chatId]);
+    const wsMsg = JSON.stringify({ type: 'new_message', payload: fullMsg });
+    for (const m of members) {
+      const sockets = connections.get(m.user_id);
+      if (sockets) sockets.forEach((ws: any) => { try { if (ws.readyState === 1) ws.send(wsMsg); } catch {} });
+    }
+
+    await pool.query('UPDATE chat_members SET last_read_at = NOW() WHERE chat_id = $1 AND user_id = $2', [chatId, userId]);
+
+    return reply.status(201).send(fullMsg);
+  });
+
   // Upload file and send as message
   app.post('/chat/:chatId/upload', async (req, reply) => {
     const { id: userId } = req.user as { id: string };