fix: add edit button, bypass constraints on manual sync

- Add Edit icon to PairDetailScreen top bar
- Wire onEdit callback through NavGraph to AddPairScreen with pairId
- Manual "Sync now" (home card + detail screen) now ignores wifiOnly
  and chargingOnly constraints so it runs immediately on tap

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/src/main/kotlin/com/syncflow/ui/home/HomeViewModel.kt

@@ -23,7 +23,7 @@ class HomeViewModel @Inject constructor(
         .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), emptyList())
 
     fun triggerSync(pair: SyncPairEntity) {
-        val req = SyncWorker.buildOneTimeRequest(pair.id, pair.wifiOnly, pair.chargingOnly)
+        val req = SyncWorker.buildOneTimeRequest(pair.id, wifiOnly = false, chargingOnly = false)
         workManager.enqueue(req)
     }