feat(a11y,admin): skip link, aria-labels, Ready label, title + age fixes

A11y:
- Skip-to-content link lands first in the body and jumps to #main
  past the header + sidebar for keyboard users.
- aria-label on the icon buttons that previously carried only an
  icon: hamburger menu (+ aria-controls="sidebar"), mobile search
  toggle, account menu (also drops the duplicate alt on the avatar
  since the button name already speaks the user's name).

Admin:
- Dashboard stat card renamed "Live Videos" → "Ready" (matches the
  DB status column; nothing on this card is actually live).

Settings:
- Duplicate "Prefer not to say" option on the Gender select — the
  empty placeholder shared the same label as the real option.
  Placeholder is now "Select…"; the real "Prefer not to say" option
  stays unchanged.
- Birthday picker caps the Year dropdown at (this year − 13) and
  the server-side register validation requires the same, so a
  client bypass can't let a <13 user through.

Titles:
- Admin layout uses "{Page} | TAKEONE" to match the frontend format
  (was "{Page} — TAKEONE"). User pages that said "| TAKEONE" literal
  now interpolate config('app.name'). Shorts and Welcome moved from
  " - " to " | " separator.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

resources/views/layouts/app.blade.php

@@ -1218,6 +1218,20 @@
     <script src="{{ asset('fp.js') }}" async></script>
 </head>
 <body class="{{ $bodyClass ?? '' }} {{ session('impersonator_id') ? 'has-impersonate-bar' : '' }}">
+    {{-- Skip link: keyboard users land here first and can jump straight to
+         the main content region, past the header + sidebar nav. Hidden
+         off-screen until focused. --}}
+    <a href="#main" class="skip-to-content">Skip to content</a>
+    <style>
+        .skip-to-content {
+            position: absolute; top: -40px; left: 8px;
+            padding: 8px 14px; z-index: 10000;
+            background: #ef4444; color: #fff; border-radius: 0 0 8px 8px;
+            text-decoration: none; font-weight: 600;
+            transition: top .15s ease;
+        }
+        .skip-to-content:focus { top: 0; outline: 2px solid #fff; outline-offset: 2px; }
+    </style>
     <!-- Header -->
     @include('layouts.partials.header')