Apply remaining audit fixes; document radii and code palette in DESIGN.md

- Token sweep: exact-value gold literals now use --wg-border /
  --wg-border-soft / --wg-focus
- Topbar: drop invalid role="menuitem" (no parent role="menu")
- topics_list: topic-select icons get role="checkbox", tabindex,
  aria-label; client.js makes them keyboard-operable and syncs
  aria-checked
- category.tpl: copy-handle link gets an accessible name, "View
  Original" moved to i18n, external-link icon aria-hidden, stretched
  link inside aria-hidden alert removed from tab order
- Footer: all copy moved to [[westgate:footer.*]] keys; year injected
  via filter:middleware.renderFooter instead of hard-coded 2026
- client.js: batch table measurements before writes (no interleaved
  reflow), .catch on the category class map so search results never
  hang, category selector match uses fw-bold class instead of inline
  style
- Forced-colors focus fallback: transparent outline alongside the
  box-shadow focus ring
- DESIGN.md: real radius scale (3/4/6/8px), code-block palette,
  motion & modes section, placeholder alpha

Verified against the sow-nodebb dev container: themed code blocks
render in posts, footer i18n + year, checkbox roles in served HTML.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

templates/category.tpl

@@ -21,8 +21,8 @@
 				</span>
 				{{{ if !isNumber(cid) }}}
 				<a href="{./url}" class="badge text-body border border-gray-300 text-xs" data-ajaxify="false">
-					<span class="fw-normal">View Original</span>
-					<i class="fa fa-external-link"></i>
+					<span class="fw-normal">[[westgate:view-original]]</span>
+					<i class="fa fa-external-link" aria-hidden="true"></i>
 				</a>
 				{{{ end }}}
 				{{{ if (!feeds:disableRSS && rssFeedUrl) }}}
@@ -39,7 +39,7 @@
 	{{{ if ./handleFull }}}
 	<p class="text-secondary text-sm fst-italic mb-0 {{{ if config.theme.centerHeaderElements }}}text-center{{{ end }}}">
 		[[category:handle.description, {handleFull}]]
-		<a href="#" class="link-secondary" data-action="copy" data-clipboard-text="{handleFull}"><i class="fa fa-fw fa-copy" aria-hidden="true"></i></a>
+		<a href="#" class="link-secondary" data-action="copy" data-clipboard-text="{handleFull}" aria-label="[[westgate:copy-handle]]"><i class="fa fa-fw fa-copy" aria-hidden="true"></i></a>
 	</p>
 	{{{ end }}}
 
@@ -65,7 +65,7 @@
 		<div class="alert alert-warning mb-4" id="category-no-followers" data-bs-toggle="dropdown" data-bs-target='[component="topic/watch"] button' aria-hidden="true">
 			<i class="fa fa-triangle-exclamation pe-2"></i>
 			[[category:no-followers]]
-			<a href="#" class="stretched-link"></a>
+			<a href="#" class="stretched-link" tabindex="-1"></a>
 		</div>
 		{{{ end }}}