feat: optimize network stack (#404)

* feat: optimize network stack and connection management

Refactor OkHttp connection pools, consolidate Gson serialization, add network-aware WebSocket reconnects, and deduplicate concurrent requests.

* test: update mapping assertions for AuthExpired

* refactor: address PR review feedback on network stack

Simplify health check, improve authenticator cookie matching robustness, resolve nit imports, and add unit tests.

app/src/main/java/com/m57/hermescontrol/ui/common/ViewModelExt.kt

@@ -4,6 +4,7 @@ import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import com.m57.hermescontrol.data.remote.NetworkResult
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 
@@ -12,17 +13,19 @@ interface ToastHost {
 }
 
 inline fun <T> ViewModel.safeLaunchLoad(
+    currentJob: Job? = null,
     crossinline apiCall: suspend () -> NetworkResult<T>,
     crossinline onStart: () -> Unit,
     crossinline onSuccess: (T) -> Unit,
     crossinline onError: (String) -> Unit,
-) {
+): Job {
+    if (currentJob?.isActive == true) return currentJob
     onStart()
-    viewModelScope.launch {
+    return viewModelScope.launch {
         val result = withContext(Dispatchers.IO) { apiCall() }
         when (result) {
             is NetworkResult.Success -> onSuccess(result.data)
-            is NetworkResult.Failure -> onError(result.error.message ?: "Unknown error")
+            is NetworkResult.Failure -> onError(result.error.message)
         }
     }
 }