Fix locale picker navigation in docs pages

The JS was trying to replace '/docs/' in the URL path, but GitHub Pages
serves docs/ as root so the live URL never contains '/docs/'. Use the
same base-path approach as the other agent-lab repos.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: brunoborges

docs/index.html

@@ -188,8 +188,8 @@ <h2 class="section-title">Prerequisites</h2>
           var t=li.dataset.locale==='pt-BR'?'pt_BR':li.dataset.locale;
           if(t===locale){close();return;}
           var p=location.pathname;
-          if(locale!=='en')p=p.replace(new RegExp('/'+locale+'/'),'/');;
-          if(t!=='en')p=p.replace(/\/docs\//,'/docs/'+t+'/');
+          if(locale!=='en')p=p.replace(new RegExp('/'+locale+'/'),'/');
+          if(t!=='en'){var base=p.replace(/\/index\.html$/,'/');if(!base.endsWith('/'))base+='/';p=base+t+'/';}
           localStorage.setItem('preferred-locale',t);
           window.location.href=p+location.search;
         });

docs/step.html

@@ -368,8 +368,8 @@ <h1>Error Loading Content</h1>
           var t=li.dataset.locale==='pt-BR'?'pt_BR':li.dataset.locale;
           if(t===locale){close();return;}
           var p=location.pathname;
-          if(locale!=='en')p=p.replace(new RegExp('/'+locale+'/'),'/');;
-          if(t!=='en')p=p.replace(/\/docs\//,'/docs/'+t+'/');
+          if(locale!=='en')p=p.replace(new RegExp('/'+locale+'/'),'/');
+          if(t!=='en'){var base=p.replace(/\/index\.html$/,'/');if(!base.endsWith('/'))base+='/';p=base+t+'/';}
           localStorage.setItem('preferred-locale',t);
           window.location.href=p+location.search;
         });