Refactor admin pages to use shared head and navigation components

- Created `admin-head.php` for consistent <head> markup across admin pages.
- Created `admin-nav.php` for shared navigation bar, reducing duplication.
- Updated all admin pages (account, hours, index, login, menu, users) to utilize the new components.
- Added security headers to `auth.php` and `index.php` for improved security.
- Introduced `security-headers.php` to manage security headers across the application.
- Moved inline styles from admin pages to SCSS files to comply with Content Security Policy (CSP).
- Normalized file permissions during build process to prevent permission issues on deployment.

menu.php

@@ -3,6 +3,8 @@ declare(strict_types=1);
 
 require __DIR__ . '/config.php';
 require __DIR__ . '/inc/assets.php';
+require __DIR__ . '/inc/security-headers.php';
+send_security_headers();
 require __DIR__ . '/inc/announcements.php';
 require __DIR__ . '/inc/menu.php';
 require __DIR__ . '/inc/hours.php';
@@ -94,24 +96,24 @@ $siteUrl = rtrim(SITE_URL, '/');
   <main id="main">
 
     <section class="menu-page-header">
-      <div class="container" style="text-align: center;">
+      <div class="container menu-hero">
         <p class="eyebrow">The Old Fitz Public House</p>
-        <h1 style="font-size: clamp(2.4rem, 5vw, 3.8rem); color: var(--gold-bright); margin-top: 0.5rem;">Pub Menu</h1>
-        <div class="rule-row" style="margin-top: 1.5rem; margin-bottom: 1.5rem;">
+        <h1 class="menu-hero-title">Pub Menu</h1>
+        <div class="rule-row menu-hero-rule">
           <span class="line"></span>
           <img class="knot" src="./assets/knot.png" alt="">
           <span class="line"></span>
         </div>
-        <p class="muted" style="max-width: 52ch; margin: 0 auto; font-size: 1.05rem;">
+        <p class="muted menu-hero-intro">
           Traditional Irish staples, shareable plates, and comforting pub classics cooked fresh. Kitchen serves until 9:00 PM.
         </p>
       </div>
     </section>
 
-    <section class="menu-page-content" style="padding-top: 0;">
-      <div class="container" style="max-width: 62rem;">
+    <section class="menu-page-content">
+      <div class="container menu-page-container">
         <?php if ($menuEnabled && !empty($menuCategories)): ?>
-          <div class="menu-grid" style="margin-top: 0;">
+          <div class="menu-grid menu-grid-flush">
             <?php foreach ($menuCategories as $category): ?>
               <?php if (!empty($category['items'])): ?>
                 <div class="menu-category">
@@ -144,17 +146,17 @@ $siteUrl = rtrim(SITE_URL, '/');
             <?php endforeach; ?>
           </div>
         <?php else: ?>
-          <div class="panel" style="text-align: center; padding: 3rem 1.5rem;">
+          <div class="panel menu-empty">
             <p class="muted">Our kitchen menu is currently being refreshed. Please check our Facebook page for today's specials!</p>
           </div>
         <?php endif; ?>
 
         <!-- Allergen / Food Safety Disclaimer from the original print menu -->
-        <div class="menu-disclaimer" style="margin-top: 3.5rem; text-align: center; padding-top: 2rem; border-top: 1px solid var(--rule);">
-          <p class="muted" style="font-size: 0.8rem; line-height: 1.6; max-width: 68ch; margin: 0 auto;">
+        <div class="menu-disclaimer">
+          <p class="muted menu-disclaimer-text">
             Consuming raw or undercooked meats, poultry, seafood, shellfish, or eggs may increase your risk of foodborne illness. Our kitchen handles a variety of ingredients, and our menu items may contain or come into contact with common allergens such as milk, eggs, wheat, soy, nuts, or shellfish.
           </p>
-          <div class="hero-ctas" style="margin-top: 2rem; justify-content: center;">
+          <div class="hero-ctas menu-disclaimer-ctas">
             <a class="btn btn-primary" href="https://www.facebook.com/profile.php?id=100086635646712" target="_blank" rel="noopener">See Daily Specials on Facebook</a>
             <a class="btn btn-outline" href="mailto:info@theoldfitzpub.com">Ask a Kitchen Question</a>
           </div>