a11y: exported semantics (forms/rating/nav/iframe/icons)

- InputField/TextareaField/ContactForm: every control gets a
  deterministic id (slugId() in utils/escape.ts, derived from the
  field's name/label + index for ContactForm's looped fields -- no
  Math.random) with a matching <label for=>; fields with no visible
  label get an aria-label from the placeholder/name instead.
- StarRating: wrapped in role="img" aria-label="Rating: N out of M",
  individual star glyphs marked aria-hidden.
- Navbar: the mobile hamburger toggle gets aria-label="Toggle
  navigation menu", aria-controls="navbar-links", and aria-expanded
  wired to flip true/false in the inline onclick handler.
- VideoBlock and MapEmbed: every exported <iframe> gets a title
  (generic "Embedded video", or "Map of {address}" for MapEmbed).
- Decorative Font Awesome icons (ContentSlider arrows already covered
  in the prior commit; SocialLinks, SearchBar, Testimonials stars) are
  aria-hidden; SocialLinks' icon-only links get an aria-label naming
  the platform alongside the existing title tooltip.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

craft/src/components/basic/Navbar.tsx

@@ -264,9 +264,12 @@ Navbar.craft = {
     return `<a href="${escapeAttr(safeUrl(link.href || "#"))}"${target}${linkStyle ? ` style="${linkStyle}"` : ''}>${escapeHtml(link.text)}</a>`;
   }).join('\n      ');
 
-  // Hamburger HTML for mobile
+  // Hamburger HTML for mobile. The toggle needs an accessible name (there's
+  // no visible text, just three bars) and must report its open/closed state
+  // via aria-expanded, kept in sync with the .navbar-open class by the
+  // inline onclick handler.
   const hamburgerHtml = mobile
-    ? `\n    <button class="navbar-hamburger" onclick="this.parentElement.querySelector('.navbar-links').classList.toggle('navbar-open')" style="display:none;background:none;border:none;cursor:pointer;padding:4px;flex-direction:column;gap:4px">
+    ? `\n    <button class="navbar-hamburger" aria-label="Toggle navigation menu" aria-expanded="false" aria-controls="navbar-links" onclick="var m=this.parentElement.querySelector('.navbar-links');var open=m.classList.toggle('navbar-open');this.setAttribute('aria-expanded', open ? 'true' : 'false');" style="display:none;background:none;border:none;cursor:pointer;padding:4px;flex-direction:column;gap:4px">
       <span style="display:block;width:24px;height:2px;background-color:${escapeAttr(textCol)}"></span>
       <span style="display:block;width:24px;height:2px;background-color:${escapeAttr(textCol)}"></span>
       <span style="display:block;width:24px;height:2px;background-color:${escapeAttr(textCol)}"></span>
@@ -305,7 +308,7 @@ Navbar.craft = {
     html: `${hoverCss}
 <nav${navStyle ? ` style="${navStyle}${mobile ? ';position:relative' : ''}"` : ''}>
   ${logoHtml}${hamburgerHtml}
-  <div class="navbar-links" style="display:flex;align-items:center;gap:24px">
+  <div class="navbar-links" id="navbar-links" style="display:flex;align-items:center;gap:24px">
       ${linksHtmlWithClass}
   </div>
 </nav>`,