refactor: replace welcome message with server_info status payload

Unify the initial connection handshake and capability update paths.
The server now sends a server_info status message on connect and
whenever capabilities change, enabling the onboarding flow where
voice becomes available after models are configured.

packages/app/src/components/message-input.tsx

@@ -356,7 +356,6 @@ export const MessageInput = forwardRef<MessageInputRef, MessageInputProps>(funct
     serverInfo,
     mode: 'dictation',
   })
-  const dictationReadiness = serverInfo?.capabilities?.voice?.dictation ?? null
 
   const canStartDictation = useCallback(() => {
     const socketConnected = client?.isConnected ?? false
@@ -416,28 +415,7 @@ export const MessageInput = forwardRef<MessageInputRef, MessageInputProps>(funct
   }, [dictationStatus, isDictating, isDictationProcessing])
 
   const startDictationIfAvailable = useCallback(async () => {
-    console.info(
-      `[DictationGate] start requested ${JSON.stringify({
-        serverId: voiceServerId ?? null,
-        agentId: voiceAgentId ?? null,
-        socketConnected: client?.isConnected ?? false,
-        isReadyForDictation: isReadyForDictation ?? null,
-        disabled,
-        serverInfoPresent: Boolean(serverInfo),
-        capabilitiesPresent: Boolean(serverInfo?.capabilities),
-        dictationReadinessEnabled: dictationReadiness?.enabled ?? null,
-        dictationReadinessReason: dictationReadiness?.reason ?? null,
-        dictationUnavailableMessage,
-      })}`
-    )
     if (dictationUnavailableMessage) {
-      console.info(
-        `[DictationGate] blocked before start ${JSON.stringify({
-          serverId: voiceServerId ?? null,
-          agentId: voiceAgentId ?? null,
-          dictationUnavailableMessage,
-        })}`
-      )
       isDictatingRef.current = false
       toast.error(dictationUnavailableMessage)
       return
@@ -446,18 +424,7 @@ export const MessageInput = forwardRef<MessageInputRef, MessageInputProps>(funct
     // state-ref sync effect, so a rapid second toggle routes to confirm.
     isDictatingRef.current = true
     await startDictation()
-  }, [
-    client,
-    dictationReadiness,
-    dictationUnavailableMessage,
-    disabled,
-    isReadyForDictation,
-    serverInfo,
-    startDictation,
-    toast,
-    voiceAgentId,
-    voiceServerId,
-  ])
+  }, [dictationUnavailableMessage, startDictation, toast])
 
   // Animate overlay
   useEffect(() => {