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/ui/layouts/splash/splash_layout.dart

@@ -0,0 +1,21 @@
+import 'package:flutter/material.dart';
+
+class SplashLayout extends StatelessWidget {
+  const SplashLayout({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return const Scaffold(
+      body: Center(
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: [
+            CircularProgressIndicator(),
+            SizedBox(height: 20),
+            Text('Checking...'),
+          ],
+        ),
+      ),
+    );
+  }
+}