feat(expressions): pickers and upload for emojis and stickers

Completes the feature: the tables existed but nothing could be put in them.

Space settings gain an Emojis & Stickers panel behind MANAGE_SPACE, with a
512KB ceiling — both are fetched on every message that uses them, so weight
matters more than fidelity. The suggested name is pre-normalised so the common
case needs no typing, and a name collision reports itself distinctly from an
upload failure: the corrective action is different.

Custom emojis join the emoji picker as their own category. They have no native
character, so selecting one inserts :name: — the same text the renderer
resolves back to an image, which also means copying a message yields something
that still reads.

Stickers get a picker tab that only appears inside a space, since that is where
they exist, and send immediately on click: a sticker is the whole message, so
parking it in the composer to await Enter would make no sense.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

packages/web/src/i18n/locales/pt-BR.ts

@@ -55,6 +55,26 @@ export const ptBR: Partial<Dictionary> = {
   'accountMenu.copyId': 'Copiar ID do usuário',
   'accountMenu.copied': 'Copiado',
 
+  // Emojis e figurinhas
+  'expressions.title': 'Emojis e figurinhas',
+  'expressions.emojis': 'Emojis',
+  'expressions.stickers': 'Figurinhas',
+  'expressions.addEmoji': 'Adicionar emoji',
+  'expressions.addSticker': 'Adicionar figurinha',
+  'expressions.emptyEmojis': 'Nenhum emoji próprio ainda.',
+  'expressions.emptyStickers': 'Nenhuma figurinha ainda.',
+  'expressions.namePrompt': 'Nome',
+  'expressions.nameHintEmoji': 'Letras, números e sublinhado. Usado como :nome: nas mensagens.',
+  'expressions.confirm': 'Adicionar',
+  'expressions.cancel': 'Cancelar',
+  'expressions.remove': 'Remover',
+  'expressions.tooLarge': 'A imagem precisa ter menos de 512 KB.',
+  'expressions.uploadFailed': 'Não foi possível adicionar essa imagem. Tente outra.',
+  'expressions.nameTaken': 'Esse nome já está em uso neste servidor.',
+  'expressions.uploading': 'Enviando…',
+  'expressions.pickerTitle': 'Figurinhas',
+  'expressions.pickerEmpty': 'Este servidor ainda não tem figurinhas.',
+
   // Busca
   'search.placeholder': 'Buscar mensagens…',
   'search.filters': 'Filtros',