refactor(chat): slim the selection menu down to comment and notes

Add to input leaves the desktop menu (mod+L owns it; mobile keeps the
button) and the New session action is gone from both variants along with
its handler and dead locale keys.

packages/ui/src/lib/i18n/messages/pt-BR.ts

@@ -2184,10 +2184,8 @@ export const dict: Record<I18nKey, string> = {
   "chat.textSelection.title.commentOnSelection": "Comentar a seleção",
   "chat.textSelection.comment.placeholder": "Adicione um comentário opcional...",
   "chat.textSelection.comment.attach": "Anexar",
-  "chat.textSelection.actions.newSession": "Nova sessão",
   "chat.textSelection.actions.addToNotes": "Adicionar às notas",
   "chat.textSelection.title.addToCurrentChat": "Adicionar ao chat atual",
-  "chat.textSelection.title.newSessionWithSelection": "Criar nova sessão com seleção",
   "chat.textSelection.title.saveInsightToNotes": "Salvar texto selecionado em notas",
   "chat.messageBody.actions.revertAria": "Voltar para esta mensagem",
   "chat.messageBody.actions.revert": "Voltar daqui",