Fix voice command status transitions and UI bugs

Fixed multiple issues with voice command workflow:

**Status Transition Fixes:**
- Fixed infinite loop in status update useEffect by checking if status actually needs to change
- Status now properly transitions: listening → understanding → review/close
- Added debug logging to track status changes

**UI Bug Fixes:**
- Fixed crash in diaper tracker when conditions field is undefined (voice-created activities)
- Auto-close dialog when classification returns "unknown" type
- Added optional chaining for conditions.join() in getDiaperDetails

**Changes:**
- VoiceFloatingButton: Prevent setting same status repeatedly
- VoiceFloatingButton: Close dialog on unknown classification
- Diaper page: Handle missing conditions field gracefully

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

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

maternal-web/app/track/diaper/page.tsx

@@ -331,9 +331,12 @@ export default function DiaperTrackPage() {
   const getDiaperDetails = (activity: Activity) => {
     const data = activity.data as DiaperData;
     const typeLabel = data.diaperType.charAt(0).toUpperCase() + data.diaperType.slice(1);
-    const conditionsLabel = data.conditions.join(', ');
+    const conditionsLabel = data.conditions?.join(', ') || '';
 
-    let details = `${typeLabel} - ${conditionsLabel}`;
+    let details = typeLabel;
+    if (conditionsLabel) {
+      details += ` - ${conditionsLabel}`;
+    }
 
     if (data.hasRash) {
       details += ` - Rash (${data.rashSeverity})`;