dsh: pin models to reliable OmniRoute providers (chat=opencode-go flash, reasoning=deepseek flash, coding=deepseek pro) + friendly labels

dsh/templates/chat.html

@@ -137,7 +137,7 @@
       try {
         const d = await (await fetch('/api/models')).json();
         (d.current || []).forEach(m => {
-          const o = document.createElement('option'); o.value = m; o.textContent = m;
+          const o = document.createElement('option'); o.value = m; o.textContent = (d.labels && d.labels[m]) || m;
           if (m === d.default) o.selected = true;
           modelSel.appendChild(o);
         });