replace: swap prosappweb content for prosapp_web_app (more complete version)

prosapp_web_app has chat, dashboard, calendar, support, 13 providers and
Fluro URL routing. Keep Dockerfile + nginx.conf from previous prosappweb.
Upgrade google_fonts 6.2.1 → 8.1.0 (Dart 3.12 compat fix).

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

lib/router/no_page_found_handlers.dart

@@ -0,0 +1,15 @@
+import 'package:prosapp_web_app/providers/sidemenu_provider.dart';
+import 'package:prosapp_web_app/ui/views/no_page_found_view.dart';
+import 'package:fluro/fluro.dart';
+import 'package:provider/provider.dart';
+
+class NoPageFoundHandlers {
+  static Handler noPageFound = Handler(
+    handlerFunc: (context, params) {
+      Provider.of<SideMenuProvider>(context!, listen: false)
+          .setCurrentPageUrl('/404');
+
+      return const NoPageFoundView();
+    },
+  );
+}