fix: enable Go to Dashboard button on setup wizard final step

The button was permanently disabled on Step 5 because canGoNext is false
when step === STEPS.length - 1. Changed disabled condition to
(!canGoNext && !isLast) so the final step bypasses canGoNext validation
while preserving it on steps 1-4.

Fixes GRO-373
Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/web/src/pages/SetupWizard.jsx

@@ -204,7 +204,7 @@ export function SetupWizard() {
           )}
           <button
             onClick={handleNext}
-            disabled={!canGoNext || loading}
+            disabled={(!canGoNext && !isLast) || loading}
             style={{
               padding: "0.55rem 1.25rem",
               borderRadius: 8,