feat(ui): render application templates as Vue views mounted before wiring

Templates listed in build/applicationViews.js expand to mount hosts, and
mountApplicationViews() renders them before translation and wiring. Markup
tests read the page through a server-side render helper, the i18n scanner
reads view templates, and Vue preserves whitespace so views keep the exact
DOM. No template is converted yet.

src/mapSourceFocus.test.mjs

@@ -1,5 +1,5 @@
 import { shellMethod } from './testSupport/readShellSource.mjs';
-import { expandApplicationHtml } from '../build/application-html.js';
+import { renderApplicationHtml } from './testSupport/applicationHtml.mjs';
 import { createHoverDisclosure, collapsePanelOnEscape } from './ui/panelDisclosure.js';
 import test from 'node:test';
 import assert from 'node:assert/strict';
@@ -7,7 +7,7 @@ import { readFileSync } from 'node:fs';
 import { msg, t } from './i18n/index.js';
 
 // Exercise the installed event routes and central close method, without WebGL.
-const markup = expandApplicationHtml(readFileSync(new URL('../index.html', import.meta.url), 'utf8'));
+const markup = await renderApplicationHtml(readFileSync(new URL('../index.html', import.meta.url), 'utf8'));
 const locationMarkup = markup.slice(markup.indexOf('<div id="location-bar"'), markup.indexOf('<div id="left-panel-stack"'));
 const locationToggleMarkup = locationMarkup.match(/<button\b([^>]*\bid="location-bar-toggle"[^>]*)>([\s\S]*?)<\/button>/);
 const locationToggleAttributes = Object.fromEntries(