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/core/admin/admin_guard.dart

@@ -0,0 +1,24 @@
+import '../../features/auth/domain/app_user.dart';
+import '../../features/profile/domain/user_profile.dart';
+
+/// Hardcoded admin allow-list for the MVP. Email match is the primary signal
+/// because the hardcoded admin doesn't carry a Firestore role document.
+const Set<String> _adminEmails = <String>{'philip@theguzmanfamily.com'};
+
+/// Returns true if [user] is on the email allow-list. Primary entry point —
+/// most callers only have an [AppUser] in hand.
+bool isAdmin(AppUser? user) {
+  if (user == null) return false;
+  final email = user.email.trim().toLowerCase();
+  if (email.isEmpty) return false;
+  return _adminEmails.contains(email);
+}
+
+/// Returns true when admin status is established either by email allow-list
+/// or by a Firestore profile document carrying [UserRole.admin]. Use this in
+/// places where a profile is already loaded so a future Firestore-driven
+/// admin grant works without a code change.
+bool isAdminWithProfile(AppUser? user, UserProfile? profile) {
+  if (isAdmin(user)) return true;
+  return profile?.role == UserRole.admin;
+}