fix: harden TrustHosts middleware and use base_url() for password reset links

- Fix circular cache dependency in TrustHosts where handle() checked cache
  before hosts() could populate it, causing host validation to never activate
- Validate both Host and X-Forwarded-Host headers against trusted hosts list
  (X-Forwarded-Host is checked before TrustProxies applies it to the request)
- Use base_url() instead of url() for password reset link generation so the
  URL is derived from server-side config (FQDN / public IP) instead of the
  request context
- Strip port from X-Forwarded-Host before matching (e.g. host:443 → host)
- Add tests for host validation, cache population, and reset URL generation

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

tests/Feature/ResetPasswordUrlTest.php

@@ -0,0 +1,123 @@
+<?php
+
+use App\Models\InstanceSettings;
+use App\Models\User;
+use App\Notifications\TransactionalEmails\ResetPassword;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\Cache;
+use Illuminate\Support\Once;
+
+uses(RefreshDatabase::class);
+
+beforeEach(function () {
+    Cache::forget('instance_settings_fqdn_host');
+    Once::flush();
+});
+
+function callResetUrl(ResetPassword $notification, $notifiable): string
+{
+    $method = new ReflectionMethod($notification, 'resetUrl');
+
+    return $method->invoke($notification, $notifiable);
+}
+
+it('generates reset URL using configured FQDN, not request host', function () {
+    InstanceSettings::updateOrCreate(
+        ['id' => 0],
+        ['fqdn' => 'https://coolify.example.com', 'public_ipv4' => '65.21.3.91']
+    );
+    Once::flush();
+
+    $user = User::factory()->create();
+    $notification = new ResetPassword('test-token-abc', isTransactionalEmail: false);
+
+    $url = callResetUrl($notification, $user);
+
+    expect($url)
+        ->toStartWith('https://coolify.example.com/')
+        ->toContain('test-token-abc')
+        ->toContain(urlencode($user->email))
+        ->not->toContain('localhost');
+});
+
+it('generates reset URL using public IP when no FQDN is configured', function () {
+    InstanceSettings::updateOrCreate(
+        ['id' => 0],
+        ['fqdn' => null, 'public_ipv4' => '65.21.3.91']
+    );
+    Once::flush();
+
+    $user = User::factory()->create();
+    $notification = new ResetPassword('test-token-abc', isTransactionalEmail: false);
+
+    $url = callResetUrl($notification, $user);
+
+    expect($url)
+        ->toContain('65.21.3.91')
+        ->toContain('test-token-abc')
+        ->not->toContain('evil.com');
+});
+
+it('is immune to X-Forwarded-Host header poisoning when FQDN is set', function () {
+    InstanceSettings::updateOrCreate(
+        ['id' => 0],
+        ['fqdn' => 'https://coolify.example.com', 'public_ipv4' => '65.21.3.91']
+    );
+    Once::flush();
+
+    // Simulate a request with a spoofed X-Forwarded-Host header
+    $user = User::factory()->create();
+
+    $this->withHeaders([
+        'X-Forwarded-Host' => 'evil.com',
+    ])->get('/');
+
+    $notification = new ResetPassword('poisoned-token', isTransactionalEmail: false);
+    $url = callResetUrl($notification, $user);
+
+    expect($url)
+        ->toStartWith('https://coolify.example.com/')
+        ->toContain('poisoned-token')
+        ->not->toContain('evil.com');
+});
+
+it('is immune to X-Forwarded-Host header poisoning when using IP only', function () {
+    InstanceSettings::updateOrCreate(
+        ['id' => 0],
+        ['fqdn' => null, 'public_ipv4' => '65.21.3.91']
+    );
+    Once::flush();
+
+    $user = User::factory()->create();
+
+    $this->withHeaders([
+        'X-Forwarded-Host' => 'evil.com',
+    ])->get('/');
+
+    $notification = new ResetPassword('poisoned-token', isTransactionalEmail: false);
+    $url = callResetUrl($notification, $user);
+
+    expect($url)
+        ->toContain('65.21.3.91')
+        ->toContain('poisoned-token')
+        ->not->toContain('evil.com');
+});
+
+it('generates a valid route path in the reset URL', function () {
+    InstanceSettings::updateOrCreate(
+        ['id' => 0],
+        ['fqdn' => 'https://coolify.example.com']
+    );
+    Once::flush();
+
+    $user = User::factory()->create();
+    $notification = new ResetPassword('my-token', isTransactionalEmail: false);
+
+    $url = callResetUrl($notification, $user);
+
+    // Should contain the password reset route path with token and email
+    expect($url)
+        ->toContain('/reset-password/')
+        ->toContain('my-token')
+        ->toContain(urlencode($user->email));
+});