feat: add modular sidebarLoader to all missing pages

- Replace hardcoded inline sidebar markup with <div id="sidebar-container">
  on: aboutMain, newsMain, productMain, serviceMain, contactMain
- Add sidebar-container + sidebarLoader.js script to pages that had no
  sidebar at all: newsArticle1, newsArticle2, productSeparateCommerceLNG,
  productSeparateCommercePNG, productSeparateProductionPRU,
  productSeparateProductionGasMeter, productSeparateProductionVaporizer,
  productSeparateProductionPressureRegulatorValve
- Sidebar HTML/CSS/JS is now loaded dynamically from /components/sidebar/
  on all 14 pages (mobile breakpoint ≤768px)"

views/contactPages/contactMain.html

@@ -31,62 +31,8 @@
     <!-- Header Component -->
     <div id="header"></div>
 
-    <!-- Floating Menu Button -->
-    <button class="floating-menu-btn" id="floatingMenuBtn">
-      <i class="bi bi-list"></i>
-    </button>
-
-    <!-- Sidebar Overlay -->
-    <div class="sidebar-overlay" id="sidebarOverlay"></div>
-
-    <!-- Sidebar -->
-    <div class="sidebar" id="sidebar">
-      <div class="sidebar-header">
-        <img
-          src="https://ik.imagekit.io/1e8470bv5/companyLogo.webp?updatedAt=1754143468028"
-          alt="Ky Long Logo"
-          class="sidebar-logo"
-        />
-        <button class="close-sidebar">
-          <i class="bi bi-x-lg"></i>
-        </button>
-      </div>
-
-      <nav class="sidebar-nav">
-        <a href="/" class="nav-link">TRANG CHỦ</a>
-        <a href="/aboutMain" class="nav-link">GIỚI THIỆU</a>
-        <a href="/productMain" class="nav-link">SẢN PHẨM</a>
-        <a href="/serviceMain" class="nav-link">DỊCH VỤ</a>
-        <a href="/newsMain" class="nav-link">TIN TỨC</a>
-        <a href="/contactMain" class="nav-link">LIÊN HỆ</a>
-      </nav>
-
-      <div class="sidebar-contact">
-        <div class="d-flex align-items-center mb-3">
-          <div
-            class="contact-icon2 d-flex align-items-center justify-content-center me-2"
-          >
-            <i class="bi bi-geo-alt-fill"></i>
-          </div>
-          <div>
-            <div>Lầu 12, số 27 Đinh Bộ Lĩnh,</div>
-            <div>P. Bình Thạnh, TP.Hồ Chí Minh</div>
-          </div>
-        </div>
-
-        <div class="d-flex align-items-center">
-          <div
-            class="contact-icon d-flex align-items-center justify-content-center me-2"
-          >
-            <i class="bi bi-envelope-open-fill"></i>
-          </div>
-          <div>
-            <div>Email:</div>
-            <div>info@kylongtech.com</div>
-          </div>
-        </div>
-      </div>
-    </div>
+    <!-- Sidebar Component -->
+    <div id="sidebar-container"></div>
 
     <!----- CONTACT PAGE CONTENT ----->
     <section class="contact-section container py-5 my-3 overflow-hidden">
@@ -200,6 +146,7 @@
 
     <!-- Scripts -->
     <script src="/components/header/headerLoader.js"></script>
+    <script src="/components/sidebar/sidebarLoader.js"></script>
     <script src="/components/footer/footerLoader.js"></script>
     <script src="contactPages/contactMain.js?v=1.1"></script>
   </body>