docs: folder browsing screenshots and docs; translate folder counts

Retakes the explorer screenshots on 1.4.0 (they still showed 0.4.0) and adds
the Folders view in English and Portuguese. The folder rows' file count sat
inside .xp-lnm, which the DOM translator skips, so it stayed in Portuguese
in the English UI; it is now translated explicitly.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/gui/ui/explorer.js

@@ -4,7 +4,7 @@
 // fullscreen quick look.
 
 import { renderPreview, kindOf, KIND_LABEL } from './preview.js';
-import { LOC } from './i18n.js';
+import { LOC, tr } from './i18n.js';
 
 const CAT = {
   image: ['Fotos', '🖼'], document: ['Documentos', '📄'], video: ['Vídeos', '🎞'], audio: ['Áudio', '🎵'],
@@ -352,7 +352,7 @@ export function createExplorer(deps) {
     const st = dirState(it.path);
     return `<div class="xp-lrow xp-dir" role="option" data-dir="${d}" aria-selected="${st === 'on'}" data-state="${st}" ${E.curDir === it.path ? 'data-cur="1"' : ''} title="${esc(it.path === '@carved' ? 'Arquivos encontrados por assinatura, sem pasta conhecida' : it.path)}">
       <span class="xp-chk" data-chk="1" aria-hidden="true"></span><div class="xp-lth"><span class="xp-lico xp-fico">${I.folderBig}</span></div>
-      <div class="xp-lnm"><b>${esc(it.name)}</b><small>${it.files.toLocaleString(LOC())} ${it.files === 1 ? 'arquivo' : 'arquivos'}</small></div>
+      <div class="xp-lnm"><b>${esc(it.name)}</b><small>${it.files.toLocaleString(LOC())} ${tr(it.files === 1 ? 'arquivo' : 'arquivos')}</small></div>
       <span class="xp-lcol"></span><span class="xp-lcol num">${human(it.bytes)}</span><span></span>
     </div>`;
   }
@@ -544,7 +544,7 @@ export function createExplorer(deps) {
       const c = E.fsCount;
       const here = dirState(E.path);
       const html = !fsEmpty()
-        ? `<span class="info">${c ? `<b>${c.files.toLocaleString(LOC())}</b> ${c.files === 1 ? 'arquivo' : 'arquivos'} · ${human(c.bytes)}` : 'Calculando seleção…'}</span>
+        ? `<span class="info">${c ? `<b>${c.files.toLocaleString(LOC())}</b> ${tr(c.files === 1 ? 'arquivo' : 'arquivos')} · ${human(c.bytes)}` : 'Calculando seleção…'}</span>
            <button class="btn sm" data-a="clear">Limpar seleção</button>
            ${here !== 'on' ? `<button class="btn sm" data-a="here">Marcar esta pasta</button>` : ''}
            <button class="btn primary" data-a="frec" ${c && c.files ? '' : 'disabled'}>Recuperar seleção</button>`