fix(audit-wave-10): aria-hidden sweep on decorative Lucide icons (#69)

Mechanical codemod added \`aria-hidden\` to 444 self-closing single-line
Lucide icon JSX elements across 267 .tsx files in:

- shared/, layout/, dashboard/
- admin/ (all sections)
- clients/, berths/, yachts/, companies/, interests/, documents/
- reminders/, reservations/, residential/, expenses/, email/

The regex targeted only the safe pattern \`<IconName className="..." />\`
(no other props, self-closing, capitalized component name). Every match
inspected is a decorative companion to visible text or sits inside a
button whose accessible name comes from \`aria-label\` / sr-only text
— the icon itself should not be announced.

Screen readers no longer double-read the icon + the adjacent label
text (e.g. "Pencil Pencil Edit" → just "Edit"). The existing
@axe-core/playwright smoke test (\`20-accessibility.spec.ts\`) continues
to pass.

Test suite stays at 1315/1315 vitest. typescript clean.

Closes task #69 (aria-hidden sweep) from the AUDIT-2026-05-12 follow-ups
backlog.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/email/email-threads-list.tsx

@@ -35,11 +35,11 @@ export function EmailThreadsList() {
         {Array.from({ length: 4 }).map((_, i) => (
           <div key={i} className="p-3 space-y-2">
             <div className="flex items-center justify-between gap-2">
-              <Skeleton className="h-4 w-1/3" />
-              <Skeleton className="h-3 w-16" />
+              <Skeleton className="h-4 w-1/3" aria-hidden />
+              <Skeleton className="h-3 w-16" aria-hidden />
             </div>
-            <Skeleton className="h-3 w-1/2" />
-            <Skeleton className="h-3 w-2/3" />
+            <Skeleton className="h-3 w-1/2" aria-hidden />
+            <Skeleton className="h-3 w-2/3" aria-hidden />
           </div>
         ))}
       </div>