[Gekidou] Fix & small refactor to the app entry logic and WS reconnection (#5937)

* Fix & small refactor to the app entry logic and WS reconnection

* Remove not needed log in MainActivity

* Replace async forEach with for await

* extract getClient to its own block

* replace double filter with reduce

* fix select channel on WS reconnect and user no longer belongs to current team

* feedback review on WS users actions

* Add windowFocusChanged for Android only

* on WS reconnection set team & channel if not member of current team

* reduce suggestion

* feedback review

android/app/src/main/java/com/mattermost/rnbeta/MattermostManagedModule.java

@@ -3,6 +3,7 @@ package com.mattermost.rnbeta;
 import android.app.Activity;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 
 import com.facebook.react.bridge.Arguments;
 import com.facebook.react.bridge.Promise;
@@ -10,19 +11,24 @@ import com.facebook.react.bridge.ReactApplicationContext;
 import com.facebook.react.bridge.ReactContextBaseJavaModule;
 import com.facebook.react.bridge.ReactMethod;
 import com.facebook.react.bridge.WritableMap;
+import com.facebook.react.modules.core.DeviceEventManagerModule;
 
 public class MattermostManagedModule extends ReactContextBaseJavaModule {
     private static MattermostManagedModule instance;
+    private ReactApplicationContext reactContext;
 
     private static final String TAG = MattermostManagedModule.class.getSimpleName();
 
     private MattermostManagedModule(ReactApplicationContext reactContext) {
         super(reactContext);
+        this.reactContext = reactContext;
     }
 
     public static MattermostManagedModule getInstance(ReactApplicationContext reactContext) {
         if (instance == null) {
             instance = new MattermostManagedModule(reactContext);
+        } else {
+            instance.reactContext = reactContext;
         }
 
         return instance;
@@ -32,6 +38,13 @@ public class MattermostManagedModule extends ReactContextBaseJavaModule {
         return instance;
     }
 
+    public void sendEvent(String eventName,
+                           @Nullable WritableMap params) {
+        this.reactContext
+                .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
+                .emit(eventName, params);
+    }
+
     @Override
     @NonNull
     public String getName() {