Initial commit: Flutter app + PHP/MySQL backend on Hostinger

Replaces Firebase with a self-hosted PHP/MySQL API served from
winded.prymsolutions.com. Includes full backend (schema, auth, events,
teams, brackets, suggestions, stats, media, file upload) and updated
Flutter repositories and domain models.

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

lib/features/events/application/events_notifier.dart

@@ -0,0 +1,28 @@
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+import '../domain/event.dart';
+import '../infrastructure/events_repository.dart';
+
+part 'events_notifier.g.dart';
+
+/// Holds the currently-selected event id used when navigating to the detail
+/// screen. Null when no event is selected.
+@riverpod
+class SelectedEventId extends _$SelectedEventId {
+  @override
+  String? build() => null;
+
+  void select(String? id) => state = id;
+}
+
+/// Resolves a single [Event] by id out of the events stream. Returns null
+/// while loading or if no event matches.
+@riverpod
+Event? eventById(EventByIdRef ref, String id) {
+  final events = ref.watch(eventsStreamProvider).valueOrNull;
+  if (events == null) return null;
+  for (final event in events) {
+    if (event.id == id) return event;
+  }
+  return null;
+}