feat: Phase 1 complete — Matrix login, rooms, chat, profile

- Direct m.login.password auth against matrix.m8chat.au
- Room list with unread badges, last message, timestamps
- Chat timeline (text, images, files, replies, reactions)
- Profile screen with expandable Notifications and Security sections
- Olm E2EE initialisation (web WASM bootstrap)
- Global error handler preventing Matrix SDK crashes
- GoRouter with refreshListenable (no recreation on auth change)
- Feature-first clean architecture: Riverpod + GoRouter + Drift
- Deployed to https://app2.m8chat.au

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

lib/features/spaces/presentation/spaces_screen.dart

@@ -0,0 +1,51 @@
+// Version: 1.0.0 | Created: 2026-04-01
+// Spaces screen stub — Phase 2 will implement full spaces navigation.
+
+import 'package:flutter/material.dart';
+
+class SpacesScreen extends StatelessWidget {
+  const SpacesScreen({super.key, this.embedded = false});
+
+  final bool embedded;
+
+  @override
+  Widget build(BuildContext context) {
+    final body = Center(
+      child: Padding(
+        padding: const EdgeInsets.all(32),
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: [
+            Icon(
+              Icons.dashboard_outlined,
+              size: 64,
+              color: Theme.of(context).colorScheme.onSurface.withAlpha(77),
+            ),
+            const SizedBox(height: 16),
+            Text(
+              'Spaces',
+              style: Theme.of(context).textTheme.titleMedium?.copyWith(
+                color: Theme.of(context).colorScheme.onSurface.withAlpha(153),
+              ),
+            ),
+            const SizedBox(height: 8),
+            Text(
+              'Space navigation is coming in Phase 2.',
+              textAlign: TextAlign.center,
+              style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                color: Theme.of(context).colorScheme.onSurface.withAlpha(102),
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+
+    if (embedded) return body;
+
+    return Scaffold(
+      appBar: AppBar(title: const Text('Spaces')),
+      body: body,
+    );
+  }
+}