Fix production class extraction by replacing template-literal classNames with cn()

Tailwind v4's static extractor missed classes adjacent to ${} in template
literals (e.g. `pb-8${...}`), causing missing styles in production builds.
Migrated all dynamic classNames to cn() and added a check script to prevent
regressions.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/components/action-bar.tsx

@@ -137,12 +137,14 @@ function AddModeSuggestions({
 								<li key={key}>
 									<button
 										type="button"
-										className={`flex w-full items-center justify-between px-3 py-1.5 text-left text-sm ${(() => {
-											if (isQueued) return "bg-accent/30 text-foreground";
-											if (i === suggestionIndex)
-												return "bg-accent/20 text-foreground";
-											return "text-foreground hover:bg-hover-neutral-bg";
-										})()}`}
+										className={cn(
+											"flex w-full items-center justify-between px-3 py-1.5 text-left text-foreground text-sm",
+											isQueued && "bg-accent/30",
+											!isQueued && i === suggestionIndex && "bg-accent/20",
+											!isQueued &&
+												i !== suggestionIndex &&
+												"hover:bg-hover-neutral-bg",
+										)}
 										onMouseDown={(e) => e.preventDefault()}
 										onClick={() => onClickSuggestion(result)}
 										onMouseEnter={() => onSetSuggestionIndex(i)}
@@ -502,11 +504,12 @@ export function ActionBar({
 										<li key={creatureKey(result)}>
 											<button
 												type="button"
-												className={`flex w-full items-center justify-between px-3 py-1.5 text-left text-sm ${
+												className={cn(
+													"flex w-full items-center justify-between px-3 py-1.5 text-left text-sm",
 													i === suggestionIndex
 														? "bg-accent/20 text-foreground"
-														: "text-foreground hover:bg-hover-neutral-bg"
-												}`}
+														: "text-foreground hover:bg-hover-neutral-bg",
+												)}
 												onMouseDown={(e) => e.preventDefault()}
 												onClick={() => handleBrowseSelect(result)}
 												onMouseEnter={() => setSuggestionIndex(i)}