test(desktop): scope the Windows download check to the desktop section

The Windows assertion searched the whole file, so it matched the hero download
array in the script block while the desktop section itself could carry no
Windows link at all. Match the section and assert inside it.

Also drop the translucency claim from the dark-mode changeset, since the
desktop window is now opaque on every platform.

Author: elkaix

.changeset/dark-sidebar-contrast.md

@@ -3,4 +3,4 @@
 "@pymodel/pythinker-desktop": patch
 ---
 
-Make the workspace header, session timestamps, and the settings row legible in dark mode on the translucent desktop sidebar.
+Make the workspace header, session timestamps, and the settings row legible in dark mode on the desktop sidebar.

apps/desktop/tests/packaging-config.spec.ts

@@ -86,10 +86,11 @@ describe('desktop packaging configuration', () => {
     expect(siteSource).toContain('releases/download/v${DESKTOP_VERSION}')
     expect(siteSource).not.toContain('releases/download/v0.1.0')
 
-    expect(siteSource).toContain('id="desktop"')
-    expect(siteSource).toMatch(
-      /\{[^}]*icon: '\/brand\/windows11\.svg', href: desktopDownloads\.windows[^}]*\}/u,
-    )
+    const desktopSection = siteSource.match(/<section id="desktop"[\s\S]*?<\/section>/u)
+
+    expect(desktopSection).not.toBeNull()
+    expect(desktopSection![0]).toContain(':href="desktopDownloads.windows"')
+    expect(desktopSection![0]).toContain('/brand/windows11.svg')
   })
 
   it('maps the staged Host node_modules directory as the copy root', () => {