Show onboarding stepper tooltips for active and last section

Updated OnboardingStepper to display tooltips persistently for the active section and the "Signup Now!" section, improving visibility and user guidance during onboarding flow.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: yyyort

apps/codebility/app/auth/onboarding/OnboardingStepper.tsx

@@ -120,12 +120,15 @@ export default function OnboardingStepper() {
 
                 {/* Enhanced tooltip label on hover */}
                 <div className="pointer-events-none absolute left-8 flex items-center gap-2">
-                  <div className="h-px w-3 bg-gradient-to-r from-gray-400 to-transparent opacity-0 transition-all duration-200 group-hover:w-4 group-hover:opacity-100 dark:from-gray-600" />
+                  <div className={cn(
+                    "h-px w-3 bg-gradient-to-r from-gray-400 to-transparent transition-all duration-200 dark:from-gray-600",
+                    (isLast || isActive) ? "w-4 opacity-100" : "opacity-0 group-hover:w-4 group-hover:opacity-100"
+                  )} />
                   <span
                     className={cn(
                       "whitespace-nowrap rounded-lg px-4 py-2 text-sm font-medium shadow-xl backdrop-blur-sm transition-all duration-200",
                       "border border-gray-200 bg-white/95 text-gray-900 dark:border-gray-700 dark:bg-gray-800/95 dark:text-white",
-                      "opacity-0 -translate-x-2 group-hover:translate-x-0 group-hover:opacity-100",
+                      (isLast || isActive) ? "translate-x-0 opacity-100" : "opacity-0 -translate-x-2 group-hover:translate-x-0 group-hover:opacity-100",
                       isActive && "border-blue-500/20 bg-gradient-to-r from-blue-50 to-purple-50 dark:from-blue-950/50 dark:to-purple-950/50"
                     )}
                   >