feat(mailbox): Implement tier-based dynamic expiration with real-time Alpine.js countdown

app/Livewire/Mailbox.php

@@ -223,7 +223,7 @@ class Mailbox extends Component
             'created_ip' => request()->ip(),
             'last_accessed_ip' => request()->ip(),
             'last_accessed_at' => now(),
-            'expires_at' => now()->addDays(7), // Default expiry
+            'expires_at' => now()->addDays($this->getValidityDays()),
         ]);
 
         $this->currentMailboxId = $mailbox->id;
@@ -262,7 +262,7 @@ class Mailbox extends Component
             'created_ip' => request()->ip(),
             'last_accessed_ip' => request()->ip(),
             'last_accessed_at' => now(),
-            'expires_at' => now()->addDays(7),
+            'expires_at' => now()->addDays($this->getValidityDays()),
         ]);
 
         $this->currentMailboxId = $mailbox->id;
@@ -270,6 +270,27 @@ class Mailbox extends Component
         Session::put('current_mailbox_id', $mailbox->id);
     }
 
+    /**
+     * Get mailbox lifespan in days based on user tier.
+     * Guest: 1 day, Free: 3 days, Pro: 7 days, Enterprise: 14 days.
+     */
+    protected function getValidityDays(): int
+    {
+        $user = auth()->user();
+
+        if (! $user) {
+            return 1; // Guests get 24 hours
+        }
+
+        return match (true) {
+            $user->isEnterprise() => 14,
+            $user->isAdmin() => 14, // Assuming admins get enterprise limits
+            $user->isPro() => 7,
+            $user->isFree() => 3,
+            default => 3,
+        };
+    }
+
     public function finishAutoCreation(): void
     {
         if ($this->getActiveMailboxesProperty()->isEmpty()) {