security: round 1 — quick wins (rate limiting, headers, mass assignment, logging)

- Add throttle middleware to login (5/min), portal/token-auth (10/min),
  volunteer-register (5/min), and invitation routes (10/min)
- Set Sanctum token expiration to 7 days
- Remove billing_status from UpdateOrganisationRequest (super_admin only)
- Revoke all Sanctum tokens on password reset
- Strengthen password rules: min 8 chars, mixed case, numbers
- Create SecurityHeaders middleware (X-Content-Type-Options, X-Frame-Options,
  HSTS, Referrer-Policy, Permissions-Policy)
- Fix open redirect on all 3 login pages (validate ?to= starts with /)
- Set APP_DEBUG=false in .env.example
- Log failed login attempts with email, IP, user-agent
- Log authorization failures (403) with user, IP, path, method
- Harden mass assignment: remove user_id from Person, audit fields from
  ShiftAssignment, system fields from UserInvitation $fillable
- Replace real DB records with factory make() in mail preview routes

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/routes/web.php

@@ -5,7 +5,9 @@ use App\Mail\RegistrationApprovedMail;
 use App\Mail\RegistrationConfirmationMail;
 use App\Mail\RegistrationRejectedMail;
 use App\Models\Event;
+use App\Models\Organisation;
 use App\Models\Person;
+use App\Models\User;
 use App\Models\UserInvitation;
 use Illuminate\Support\Facades\Route;
 
@@ -23,26 +25,19 @@ if (app()->environment('local', 'staging')) {
         }
 
         if ($type === 'invitation') {
-            $invitation = UserInvitation::first();
-
-            if (! $invitation) {
-                return response('No UserInvitation found in the database. Create one first to preview this mail.', 422);
-            }
+            $organisation = Organisation::factory()->make();
+            $invitation = UserInvitation::factory()->make();
+            $invitation->setRelation('organisation', $organisation);
+            $invitation->setRelation('invitedBy', User::factory()->make());
+            $invitation->token ??= 'preview-token';
+            $invitation->role ??= 'org_member';
+            $invitation->expires_at ??= now()->addDays(7);
 
             return new InvitationMail($invitation);
         }
 
-        $event = Event::first();
-        $person = Person::first();
-
-        if (! $event || ! $person) {
-            $missing = collect([
-                'Event' => $event,
-                'Person' => $person,
-            ])->filter(fn ($v) => $v === null)->keys()->implode(', ');
-
-            return response("No test data found. Missing: {$missing}. Seed the database first.", 422);
-        }
+        $event = Event::factory()->make();
+        $person = Person::factory()->make();
 
         return match ($type) {
             'registration-confirmation' => new RegistrationConfirmationMail($person, $event),