refactor: separate application UI state owners

src/mapSourceFocus.test.mjs

@@ -1,3 +1,4 @@
+import { readShellSource, shellMethod } from './testSupport/readShellSource.mjs';
 import { expandApplicationHtml } from '../build/application-html.js';
 import { StyleManager } from './ui/applicationShell.js';
 import { createHoverDisclosure, collapsePanelOnEscape } from './ui/panelDisclosure.js';
@@ -6,7 +7,7 @@ import assert from 'node:assert/strict';
 import { readFileSync } from 'node:fs';
 
 // Exercise the installed event routes and central close method, without WebGL.
-const source = readFileSync(new URL('./ui/applicationShell.js', import.meta.url), 'utf8');
+const source = readShellSource();
 const markup = expandApplicationHtml(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>/);
@@ -107,7 +108,7 @@ function harness({ hidden = false, selected = true, noChips = false } = {}) {
   window.performance = { now: () => now };
   document.defaultView = window;
   const methods = new Function('createHoverDisclosure', 'collapsePanelOnEscape', 'document', 'window', 'clearTimeout', 'performance', 'requestAnimationFrame',
-    `return ({${StyleManager.prototype._initAutoHoverPanel.toString()},\n${StyleManager.prototype._collapsePanelOnEscape.toString()},\n${StyleManager.prototype.setPanelCollapsed.toString()},\n${StyleManager.prototype._syncPanelCollapseButton.toString()}});`)(
+    `return ({${shellMethod('_initAutoHoverPanel').toString()},\n${shellMethod('_collapsePanelOnEscape').toString()},\n${shellMethod('setPanelCollapsed').toString()},\n${shellMethod('_syncPanelCollapseButton').toString()}});`)(
     createHoverDisclosure, collapsePanelOnEscape, document, window, (id) => timers.delete(id), { now: () => now }, () => {},
   );
   const saves = [];