feat: update translations

frontend/public/locales/en/chat.json

@@ -12,7 +12,6 @@
     "receivedResponse": "Received response. Starting to handle stream...",
     "errorCallingAPI": "Error calling the API",
     "ask": "Ask a question, or describe a task.",
-    "begin_conversation_placeholder": "Begin conversation here...",
     "thinking": "Thinking...",
     "chat": "Chat",
     "errorFetching": "Error occurred while fetching your chats",

frontend/public/locales/es/chat.json

@@ -1,7 +1,6 @@
 {
   "actions_bar_placeholder": "Haz una pregunta a @brains o /files y elige tu #indicación",
   "ask": "Has una pregunta o describe un tarea.",
-  "begin_conversation_placeholder": "Inicia la conversación aquí...",
   "brain": "cerebro",
   "brains": "cerebros",
   "chat": "Conversar",

frontend/public/locales/fr/chat.json

@@ -1,7 +1,6 @@
 {
   "actions_bar_placeholder": "Posez une question à @brains ou /files et choisissez votre #invite",
   "ask": "Posez une question ou décrivez une tâche.",
-  "begin_conversation_placeholder": "Commencez la conversation ici...",
   "brain": "cerveau",
   "brains": "cerveaux",
   "chat": "Chat",

frontend/public/locales/pt-br/chat.json

@@ -1,7 +1,6 @@
 {
     "actions_bar_placeholder": "Faça uma pergunta para @cérebros ou /arquivos e escolha o seu #prompt",
     "ask": "Faça uma pergunta ou descreva uma tarefa.",
-    "begin_conversation_placeholder": "Inicie a conversa aqui...",
     "brain": "cérebro",
     "brains": "cérebros",
     "chat": "Conversa",

frontend/public/locales/ru/chat.json

@@ -1,7 +1,6 @@
 {
     "actions_bar_placeholder": "Задайте вопрос @brains или /files и выберите ваш #prompt",
     "ask": "Задайте вопрос или опишите задачу.",
-    "begin_conversation_placeholder": "Начните беседу здесь...",
     "brain": "мозг",
     "brains": "мозги",
     "chat": "Чат",