feat: add Reverb realtime messaging

app/Models/Conversation.php

@@ -23,14 +23,18 @@ class Conversation extends Model
     use HasFactory;
 
     protected $fillable = [
+        'uuid',
         'type',
         'title',
         'created_by',
+        'last_message_id',
         'last_message_at',
+        'is_active',
     ];
 
     protected $casts = [
         'last_message_at' => 'datetime',
+        'is_active' => 'boolean',
     ];
 
     // ── Relationships ────────────────────────────────────────────────────────
@@ -81,6 +85,7 @@ class Conversation extends Model
     {
         return self::query()
             ->where('type', 'direct')
+            ->where('is_active', true)
             ->whereHas('allParticipants', fn ($q) => $q->where('user_id', $userA)->whereNull('left_at'))
             ->whereHas('allParticipants', fn ($q) => $q->where('user_id', $userB)->whereNull('left_at'))
             ->whereRaw(
@@ -108,6 +113,11 @@ class Conversation extends Model
             ->whereNull('deleted_at')
             ->where('sender_id', '!=', $userId);
 
+        if ($participant->last_read_message_id) {
+            $query->where('id', '>', $participant->last_read_message_id);
+            return $query->count();
+        }
+
         if ($participant->last_read_at) {
             $query->where('created_at', '>', $participant->last_read_at);
         }