Rename Random to Auto in UI and always show + on last stage

- Display "Auto" instead of "Random" for symbol/action selectors
- Last withdrawal stage always shows "+" suffix (even with one stage)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/page.tsx

@@ -494,7 +494,7 @@ export default function Home() {
                                     className="rounded-lg border border-slate-200 bg-slate-50 px-2.5 py-1.5 text-sm font-mono text-slate-800 focus:outline-none focus:ring-2 focus:ring-blue-500"
                                 >
                                     {enabledSymbols.map((s) => <option key={s} value={s}>{s}</option>)}
-                                    <option value="Random">Random</option>
+                                    <option value="Random">Auto</option>
                                 </select>
                                 <div className="flex rounded-lg border border-slate-200 overflow-hidden text-sm font-semibold">
                                     <button
@@ -513,7 +513,7 @@ export default function Home() {
                                         onClick={() => setTradeAction('Random')}
                                         className={`px-3 py-1.5 transition-colors border-l border-slate-200 ${tradeAction === 'Random' ? 'bg-purple-500 text-white' : 'text-slate-500 hover:bg-slate-50'}`}
                                     >
-                                        Random
+                                        Auto
                                     </button>
                                 </div>
                                 <div className="flex items-center gap-1.5 ml-1">