jbot: remove hint text from bottom footer — keep only the voice button

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

static_src/jbot/App.jsx

@@ -312,7 +312,6 @@ export default function App() {
   }, [handleSpaceDown, handleSpaceUp, pick]);
 
   // ── Render ─────────────────────────────────────────────────
-  const currentVoiceLabel = getVoiceLabel(getEffectiveVoice());
 
   return (
     <div className="app">
@@ -381,10 +380,6 @@ export default function App() {
           <MemoryPanel memories={memories} onMemoriesChange={refreshMemories} />
           <ChatPanel messages={chatMessages} voiceStatus={voiceStatus} />
           <div className="right-footer">
-            <p className="right-hint">
-              按住 <kbd>Space</kbd> 或按钮说话 · 松开发送 · 🔊{' '}
-              <button className="hist-inline-link" onClick={() => navigate('/settings')}>{currentVoiceLabel}</button>
-            </p>
             <VoiceButton phase={voicePhase} onStart={handleSpaceDown} onEnd={handleSpaceUp} />
           </div>
         </div>