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/chat/data/chat_repository.dart

@@ -0,0 +1,129 @@
+// Version: 1.0.1 | Created: 2026-04-01
+// Chat repository. Bridges Matrix SDK timeline to app domain models.
+// Uses room.getTimeline() — timeline is async in matrix 0.33.0.
+
+import 'package:matrix/matrix.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+import '../../../core/network/matrix_client.dart';
+import '../domain/message_model.dart';
+
+part 'chat_repository.g.dart';
+
+@riverpod
+ChatRepository chatRepository(Ref ref) {
+  return ChatRepository(client: ref.watch(matrixClientProvider));
+}
+
+class ChatRepository {
+  ChatRepository({required Client client}) : _client = client;
+
+  final Client _client;
+
+  Room? _getRoom(String roomId) => _client.getRoomById(roomId);
+
+  /// Returns a stream of message lists for [roomId].
+  ///
+  /// Opens the room's timeline once and then emits on every update.
+  /// The timeline object is closed when the stream subscription is cancelled.
+  Stream<List<MessageModel>> watchTimeline(String roomId) async* {
+    final room = _getRoom(roomId);
+    if (room == null) return;
+
+    final timeline = await room.getTimeline(
+      onUpdate: () {
+        // Handled by the stream controller below.
+      },
+    );
+
+    // Emit the initial state.
+    yield _mapTimeline(timeline, room);
+
+    // Emit on subsequent sync events that affect this room.
+    await for (final update in _client.onSync.stream) {
+      final updatesThisRoom = update.rooms?.join?.containsKey(roomId) ?? false;
+      if (updatesThisRoom) {
+        yield _mapTimeline(timeline, room);
+      }
+    }
+
+    // Clean up timeline subscriptions when the stream is cancelled.
+    timeline.cancelSubscriptions();
+  }
+
+  /// Sends a plain text message to [roomId].
+  Future<void> sendTextMessage(String roomId, String text) async {
+    final room = _getRoom(roomId);
+    if (room == null) return;
+    await room.sendTextEvent(text);
+  }
+
+  /// Sends a read receipt for the latest event in [roomId].
+  Future<void> markAsRead(String roomId) async {
+    final room = _getRoom(roomId);
+    if (room == null) return;
+    final lastEventId = room.lastEvent?.eventId ?? '';
+    if (lastEventId.isEmpty) return;
+    await room.setReadMarker(lastEventId, mRead: lastEventId);
+  }
+
+  /// Requests older messages be loaded (pagination).
+  Future<void> loadMoreMessages(String roomId) async {
+    final room = _getRoom(roomId);
+    if (room == null) return;
+    await room.requestHistory();
+  }
+
+  List<MessageModel> _mapTimeline(Timeline timeline, Room room) {
+    final myUserId = _client.userID ?? '';
+    return timeline.events
+        .map((e) => _toModel(e, timeline, myUserId))
+        .toList()
+        .reversed
+        .toList();
+  }
+
+  MessageModel _toModel(Event event, Timeline timeline, String myUserId) {
+    final senderProfile = event.room.unsafeGetUserFromMemoryOrFallback(
+      event.senderId,
+    );
+
+    return MessageModel(
+      eventId: event.eventId,
+      roomId: event.roomId ?? '',
+      senderId: event.senderId,
+      senderDisplayName:
+          senderProfile.displayName ?? event.senderId.split(':').first,
+      senderAvatarUrl: senderProfile.avatarUrl?.toString(),
+      timestamp: event.originServerTs,
+      type: _messageType(event),
+      body: event.redacted ? null : event.body,
+      mxcUrl: _extractMxcUrl(event),
+      inReplyToEventId: event.relationshipEventId,
+      isMine: event.senderId == myUserId,
+      isEdited: event.hasAggregatedEvents(timeline, RelationshipTypes.edit),
+    );
+  }
+
+  MessageType _messageType(Event event) {
+    if (event.redacted) return MessageType.redacted;
+
+    return switch (event.messageType) {
+      MessageTypes.Text => MessageType.text,
+      MessageTypes.Image => MessageType.image,
+      MessageTypes.File => MessageType.file,
+      MessageTypes.Audio => MessageType.audio,
+      MessageTypes.Video => MessageType.video,
+      MessageTypes.Sticker => MessageType.sticker,
+      _ => MessageType.unsupported,
+    };
+  }
+
+  String? _extractMxcUrl(Event event) {
+    final content = event.content;
+    if (content.containsKey('url')) {
+      return content['url'] as String?;
+    }
+    return null;
+  }
+}