Move remaining code to app module

There's still some stuff that could potentially go elsewhere but I think it's enough for now.

src/app/notifyrc.qrc

@@ -0,0 +1,9 @@
+<!--
+    SPDX-FileCopyrightText: None
+    SPDX-License-Identifier: CC0-1.0
+-->
+<RCC>
+    <qresource prefix="/knotifications6">
+        <file>neochat.notifyrc</file>
+    </qresource>
+</RCC>