fix(terminal): init payload never sent due to ws.onopen being overwritten

connectWebSocket set ws.onopen to send the shell init payload, but
initTerminal immediately overwrote it with a state-only handler.
Switched to addEventListener so both handlers coexist.

web/src/components/Shell.jsx

@@ -94,15 +94,15 @@ function connectWebSocket(term, fitAddon, initPayload) {
   const proto = window.location.protocol === 'https:' ? 'wss:' : 'ws:'
   const ws = new WebSocket(`${proto}//${window.location.host}/api/ws/terminal`)
 
-  ws.onopen = () => {
+  ws.addEventListener('open', () => {
     ws.send(JSON.stringify(initPayload))
     const dims = fitAddon.proposeDimensions()
     if (dims) {
       ws.send(JSON.stringify({ type: 'resize', rows: dims.rows, cols: dims.cols }))
     }
-  }
+  })
 
-  ws.onmessage = (event) => {
+  ws.addEventListener('message', (event) => {
     try {
       const msg = JSON.parse(event.data)
       if (msg.type === 'output') {
@@ -113,15 +113,15 @@ function connectWebSocket(term, fitAddon, initPayload) {
     } catch {
       term.write(event.data)
     }
-  }
+  })
 
-  ws.onclose = () => {
+  ws.addEventListener('close', () => {
     term.write('\r\n\x1b[33m— Connection closed —\x1b[0m\r\n')
-  }
+  })
 
-  ws.onerror = () => {
+  ws.addEventListener('error', () => {
     term.write('\r\n\x1b[31m— Connection error —\x1b[0m\r\n')
-  }
+  })
 
   term.onData((data) => {
     if (ws.readyState === WebSocket.OPEN) {