feat: the workspace at /workspace; Настройки show the assistant's model as set, key included, and PostgreSQL's fields only when chosen, its two buttons on one line; pages come in softly

internal/server/web/static/app.js

@@ -7,7 +7,7 @@
 // unmounted - its timers, requests and listeners dropped - when it goes.
 (function () {
   'use strict';
-  const views = {'/': 'machines', '/terminal': 'terminal', '/settings': 'settings'};
+  const views = {'/': 'machines', '/workspace': 'terminal', '/terminal': 'terminal', '/settings': 'settings'};
   const modules = {};
   const mounted = new Map(); // area -> {mod, scope}
   const $ = s => document.querySelector(s);
@@ -120,6 +120,8 @@
 
   // start mounts what the server drew, once every script has registered.
   function start() {
+    // The old address of the workspace shows as the new one.
+    if (location.pathname === '/terminal') { history.replaceState({}, '', '/workspace' + location.search); shown = '/workspace' + location.search; }
     document.querySelectorAll('main#app > .view').forEach(mount);
     show({dashboard: 'machines', settings: 'settings'}[$('main#app').dataset.view] || 'terminal');
     // /agents/{id}/terminal or /files: that pane, at once.