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/app/Http/Requests/Api/V1/AcceptInvitationRequest.php

@@ -7,6 +7,7 @@ namespace App\Http\Requests\Api\V1;
 use App\Models\User;
 use App\Models\UserInvitation;
 use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rules\Password;
 
 final class AcceptInvitationRequest extends FormRequest
 {
@@ -24,7 +25,7 @@ final class AcceptInvitationRequest extends FormRequest
         return [
             'first_name' => [$userExists ? 'nullable' : 'required', 'string', 'max:255'],
             'last_name' => [$userExists ? 'nullable' : 'required', 'string', 'max:255'],
-            'password' => [$userExists ? 'nullable' : 'required', 'string', 'min:8', 'confirmed'],
+            'password' => [$userExists ? 'nullable' : 'required', 'string', 'confirmed', Password::min(8)->mixedCase()->numbers()],
         ];
     }
 }

api/app/Http/Requests/Api/V1/UpdateOrganisationRequest.php

@@ -23,7 +23,6 @@ final class UpdateOrganisationRequest extends FormRequest
                 'sometimes', 'string', 'max:255', 'regex:/^[a-z0-9-]+$/',
                 Rule::unique('organisations', 'slug')->ignore($this->route('organisation')),
             ],
-            'billing_status' => ['sometimes', 'string', 'in:active,trial,suspended'],
             'settings' => ['sometimes', 'array'],
             'email_logo_url' => ['nullable', 'url', 'max:500'],
             'email_primary_color' => ['nullable', 'string', 'regex:/^#[0-9A-Fa-f]{6}$/'],

api/app/Http/Requests/Api/V1/VolunteerRegistrationRequest.php

@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace App\Http\Requests\Api\V1;
 
 use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rules\Password;
 
 final class VolunteerRegistrationRequest extends FormRequest
 {
@@ -60,7 +61,7 @@ final class VolunteerRegistrationRequest extends FormRequest
 
         // Password required for unauthenticated registrations
         if ($user === null) {
-            $rules['password'] = ['required', 'string', 'min:8'];
+            $rules['password'] = ['required', 'string', Password::min(8)->mixedCase()->numbers()];
             $rules['password_confirmation'] = ['nullable', 'same:password'];
         }